sign in sign up
<<
Home , Fidaxomicin, Lipoglycopeptide, Tedizolid

Annals of Internal Medicine MEDICINE AND PUBLIC ISSUES Progress in the Fight Against Multidrug-Resistant ? A Review of U.S. Food and Drug Administration–Approved , 2010–2015 Dalia Deak, MPH; Kevin Outterson, LLM, JD; John H. Powers, MD; and Aaron S. Kesselheim, MD, JD, MPH

A weak pipeline and the increase in drug-resistant months in FDA review (IQR, 7.5 to 8 months). The median num- pathogens have led to calls for more new antibiotics. Eight new ber of patients enrolled in the pivotal trials was 666 (IQR, 553 to antibiotics were approved by the U.S. Food and Drug Adminis- 739 patients; full range, 44 to 1005 patients), and median trial tration (FDA) between January 2010 and December 2015: cef- duration was 18 months (IQR, 15 to 22 months). Seven drugs taroline, fidaxomicin, bedaquiline, , tedizolid, orita- were approved on the basis of pivotal trials evaluating noninfe- vancin, ceftolozane–, and –. riority. One drug demonstrated superiority on an exploratory This study evaluates the development course and pivotal trials of secondary end point, 2 showed decreased efficacy in patients these antibiotics for their innovativeness, development process, with renal insufficiency, and 1 showed increased mortality com- documented patient outcomes, and cost. Data sources were pared with older drugs. Seven of the drugs are substantially FDA approval packages and databases (January 2010 to De- more expensive than their trial comparators. Limitations are that cember 2015); the Red Book (Truven Health Analytics); Orange future research may show benefit to patients; new drugs from Book: Approved Drug Products with Therapeutic Equivalence older classes may show superior effectiveness in specific patient Evaluations (FDA); and supplementary information from com- populations; and initial U.S. prices for each new antibiotic were pany filings, press releases, and media reports. Four antibiotics obtained from public sources. Recently marketed antibiotics are were approved for acute bacterial skin and skin-structure infec- more expensive but have been approved without evidence of tion. Seven had similar mechanisms of action to those of previ- clinical superiority. ously approved drugs. Six were initially developed by small to midsized companies, and 7 are currently marketed by 1 of 3 Ann Intern Med. doi:10.7326/M16-0291 www.annals.org large companies. The drugs spent a median of 6.2 years in clin- For author affiliations, see end of text. ical trials (interquartile range [IQR], 5.4 to 8.8 years) and 8 This article was published at www.annals.org on 31 May 2016.

dvances in the treatment and prevention of infec- There are signs that the antibiotic pipeline may al- Atious diseases, in part due to antibiotic develop- ready be improving (13). In 2010, the Infectious Dis- ment, are one of the greatest gains in medicine of the eases Society of America set a goal for 10 novel antibi- past century (1–4). Many have identified the increase in otics to reach the U.S. market by 2020 (20). Since then, drug-resistant pathogens as a serious threat in main- the FDA has approved 8 new antibiotics. Regulators taining these gains (5–7). Despite the need for new an- and advocates have celebrated the development and tibiotics with improved effectiveness to address resis- approval of these antibiotics (24). Does this increase in tance, many stakeholders have observed that the approvals represent important progress for patients? antibiotic pipeline is weak (8–12), although these To answer this question, we evaluated the discovery, claims may be overstated (13). Screening of naturally development course, pivotal trial results, and costs as- occurring compounds and use of advanced platforms sociated with these new drugs. to identify targets have led to few returns in recent de- cades (14). In addition, numerous large, for-profit phar- maceutical companies have ceased active antibiotic de- METHODS velopment owing to concerns about returns on Data Sources and Searches investment and the scientific challenges in antibiotic For all new antibiotics from January 2010 through discovery (10, 15, 16). December 2015, we extracted key characteristics from These developments have led to calls for a variety their approval packages by using the Drugs@FDA da- of incentives to spur development of new antibiotics, tabase (25–30). We then determined the origins of the particularly ones targeting multidrug-resistant, gram- drugs and their development, including their corporate negative bacteria (16–21). The Generating Antibiotic In- sponsorship history from company press releases and centives Now (GAIN) Act of 2012 awarded qualifying other public information. new products faster review times by the U.S. Food and We next reviewed the major steps in preclinical Drug Administration (FDA), as well as 5 additional years and clinical investigational development by collecting of market exclusivity above the approximately 7 years details associated with the FDA-designated “pivotal already guaranteed to new small-molecule drugs (22). trials” used to demonstrate efficacy. Details were In 2015, the House of Representatives passed the 21st collected from FDA reviews and reports on Clinical Century Cures Act, which would permit approval of an- Trials.gov. timicrobials on the basis of preclinical data and prelim- We identified whether the FDA imposed any post- inary studies in small numbers of patients (23). approval study requirements. We extracted postmarket

www.annals.org Annals of Internal Medicine 1 Downloaded From: http://annals.org/ by a Boston University Medical Center User on 06/01/2016 MEDICINE AND PUBLIC ISSUES FDA-Approved Antibiotics, 2010-2015

commitments or requirements from the FDA's online ceding 6 terms). We also assessed whether each drug database (31) and assessed the status of each as of was awarded any postapproval incentives. December 2015. We extracted postapproval incentives To determine the cost of each antibiotic, we calcu- from the FDA's Orange Book: Approved Drug Products lated a price range on the basis of the overall dose and with Therapeutic Equivalence Evaluations (32) and com- duration of the treatment from the average unit price pany press releases. extracted from the Red Book (33). Finally, to determine the cost of each drug for a recommended duration of course of treatment, we ob- tained the average wholesale U.S. price for each new RESULTS antibiotic and its comparator from the Red The 8 new antibiotics were ceftaroline, fidaxomicin, Book (33). bedaquiline, dalbavancin, tedizolid, , cef- tolozane–tazobactam, and ceftazidime–avibactam. Four Study Selection were approved in 2014. Five are administered intrave- We studied all new molecular entity antibiotics ap- nously and 2 orally, and 1 was approved in both formu- proved by the FDA between January 2010 and Decem- lations (Table 1). ber 2015. Mechanisms of Action and Indications Data Synthesis and Analysis Four drugs were initially indicated for acute bacte- For each drug, we assessed the mechanism of ac- rial skin and skin-structure ; 2 for complicated tion, larger , year of discovery, and approved intra-abdominal (CIAI) and complicated uri- indications. We also identified in vitro activity against nary tract infection (CUTI); and 1 each for community- ESKAPE pathogens (Enterococcus faecium, Staphylo- acquired pneumonia, C difficile–associated diarrhea, coccus aureus, Klebsiella pneumonia, Acinetobacter and multidrug-resistant tuberculosis (Table 1). Three of baumannii, , and Enterobac- the 8 drugs showed in vitro activity against ESKAPE ter species) (34, 35) and Centers for Disease Control pathogens; 1 of the drugs, fidaxomicin, demonstrated and Prevention urgent-threat pathogens ( in vitro activity against a Centers for Disease Control difficile, -resistant Enterobacteriaceae, and and Prevention urgent-threat pathogen, C difficile. drug-resistant Neisseria gonorrhoeae [ Only bedaquiline was specifically indicated for a dis- resistance]) (6), on the basis of information included in ease due to a multidrug-resistant pathogen, although the FDA approval packages. In vitro activity does not most demonstrated in vitro activity against gram- necessarily reflect benefits on actual patient clinical positive drug-resistant pathogens (38, 39). For exam- outcomes, as exemplified by such drugs as ple, although ceftaroline was found to have in vitro ac- and (36, 37). tivity against -resistant S aureus (MRSA), the To determine the corporate sponsorship history of trials used to support FDA approval for pneumonia did the antibiotics, we examined the size of the company, not specifically study efficacy in disease due to MRSA. given the different incentives that may be needed for Still, the drug received an indication for skin infections different-sized companies. We classified “large compa- due to MRSA (13, 40). nies” as those with more than 10 000 employees and Seven antibiotics fell within established drug small to midsized companies as those with 10 000 or classes, the most common being ␤-lactams (ceftaroline, fewer employees. ceftolozane–tazobactam, and ceftazidime–avibactam). In assessing pivotal clinical trials for each antibiotic, The one drug involving a new was we extracted indications, comparator drugs, end bedaquiline, a diarylquinoline targeting adenosine points, trial sizes, trial durations, and trial hypotheses triphosphate synthase to inhibit the growth of drug- (noninferiority versus superiority). We tracked primary resistant tuberculosis (39). end points of the trials, as well as FDA-recommended secondary end points (for example, a new recom- Drug Development mended end point from the guidance document). Be- Six antibiotics were initially developed by small to cause the ceftolozane–tazobactam trials relied on midsized companies, and 7 were sponsored by small to pooled data, the time for each trial was averaged with midsized companies at the time of approval (Figure). its pooling counterpart. Larger manufacturers then became involved after ap- We determined the length of time each antibiotic proval: 7 are currently marketed by 1 of 3 large com- spent in clinical development as the time from investi- panies. For example, Actavis (~17 000 employees) ac- gational new drug (IND) status (the application to begin quired dalbavancin and ceftazidine–avibactam after human trials) to new drug application (NDA) status (the smaller companies had guided these products through sponsor's full submission to FDA). Regulatory review FDA approval. In the case of dalbavancin, Pfizer time ran from the date of NDA submission to FDA ap- (~78 000 employees) acquired Vicuron Pharmaceuti- proval. We assessed whether each antibiotic qualified cals in 2005, but voluntarily withdrew the NDA for dal- for special regulatory pathways or designations, includ- bavancin. In 2009, Pfizer divested Vicuron Pharmaceu- ing qualified infectious disease product, fast track, pri- ticals, with Durata Therapeutics (<100 employees) ority review, accelerated approval, breakthrough ther- subsequently moving the drug through approval. In apy, and orphan drug designation (see the Appendix, 2014, Durata Therapeutics was acquired by Actavis, available at www.annals.org, for definitions of the pre- which then merged with Allergan.

2 Annals of Internal Medicine www.annals.org Downloaded From: http://annals.org/ by a Boston University Medical Center User on 06/01/2016 FDA-Approved Antibiotics, 2010-2015 MEDICINE AND PUBLIC ISSUES

Table 1. Antibiotic Drug Details, Development Milestones, and ESKAPE Status

Drug IND Filed NDA Approval Current Drug Class Method of Novel Indications In Vitro Filed Date Manufacturer (Year of Administration Mechanism Activity Discovery) of Action Against ESKAPE Pathogens? Ceftaroline December December 29 October Actavis Cephalosporin Intravenous No ABSSSI; CABP Yes 2004 2009 2010 (1928) Fidaxomicin August November 27 May 2011 Cubist Oral No CDAD and No* 2003 2010 Pharmaceuticals (1948) prevention (subsidiary of of Merck) recurrences Bedaquiline November June 28 Janssen Diarylquinoline Oral Yes Pulmonary No† 2006 2012 December Research and (1997) tuberculosis 2012 Development caused by (Johnson & multidrug- Johnson) resistant tuberculosis Dalbavancin July 2000 September 23 May 2014 Actavis Lipoglycopeptide Intravenous No ABSSSI No 2013 (1953) Tedizolid November October 20 June Cubist Oxazolidinone Oral; intravenous No ABSSSI No 2007; 2013 2014 Pharmaceuticals (1955) August (subsidiary of 2009 Merck) Oritavancin August December 6 August The Medicines Glycopeptide Intravenous No ABSSSI No 1996 2013 2014 Company (1953) Ceftolozane– July 2009 April 19 Cubist Cephalosporin Intravenous No CIAI; CUTI Yes tazobactam 2014 December Pharmaceuticals (1928) + 2014 (subsidiary of ␤-lactamase Merck) inhibitor Ceftazidime– January June 25 February AstraZeneca/ Cephalosporin Intravenous No CIAI; CUTI Yes avibactam 2008 2014 2015 Actavis (1928) + ␤-lactamase inhibitor ABSSSI = acute bacterial skin and skin-structure infection; CABP = community-acquired bacterial pneumonia; CDAD = Clostridium difficile–associ- ated diarrhea; CIAI = complicated intra-abdominal infection; CUTI = complicated urinary tract infection; ESKAPE = Enterococcus faecium, Staphy- lococcus aureus, Klebsiella pneumonia, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species; IND = investigational new drug; NDA = new drug application. * Clostridium difficile is a Centers for Disease Control and Prevention urgent-threat pathogen. † Multidrug-resistant tuberculosis is a global health priority.

Development Times ment of the efficacy of ceftazidime–avibactam was The antibiotics in our cohort spent a median of 6.2 based on 2 early-phase exploratory trials without pre- years between IND and NDA status (interquartile range specified hypotheses (rather than confirmatory phase 3 [IQR], 5.4 to 8.8 years) and a median of 8 months be- trials), along with previous findings of efficacy and pub- tween NDA status and FDA approval (IQR, 7.5 to 8 lished literature for ceftazidime alone and nonclinical months) (Table 1). Ceftolozane–tazobactam spent the studies and descriptive data for avibactam. Bedaquiline shortest time between IND and NDA status (4.8 years). was approved on the basis of a phase 2 trial with 2 Oritavancin had the longest development period (17.3 stages, and an uncontrolled case series (41). years), which was suspended for multiple years after Seven drugs were approved on the basis of pivotal initial trial results showed an increased rate of injection- trials designed with noninferiority hypotheses. All site inflammation and the drug failed to demonstrate drugs except for ceftazidime–avibactam had a 10% noninferiority in pivotal trials using daily dosing. Later, noninferiority margin. The 2 early-phase trials for cefta- Targanta Therapeutics Corporation acquired rights to zidime–avibactam did not have prespecified hypothe- the drug and demonstrated that the inflammation was ses with stated noninferiority margins or inferential sta- associated with high infusion rates and high drug con- tistical testing but were interpreted as demonstrating centrations, leading to approval for the drug on the noninferiority, allowing large margins of inferiority ex- basis of demonstration of noninferiority with weekly ceeding 15% to 20%. rather than daily dosing. Excluding oritavancin, the me- Tedizolid was tested based on a noninferiority hy- dian time from IND to NDA status was 5.9 years (IQR, pothesis because it was hypothesized, on the basis of 5.3 to 6.8 years). preclinical data, to have fewer adverse effects than lin- Characteristics of Trials Used to Support ezolid. However, no hypotheses examined patient ben- Approval efits other than improved effectiveness for any of the The median number of patients enrolled in the piv- other noninferiority studies, despite benefits other than otal trials was 666 (IQR, 553 to 739; full range, 44 to improved effectiveness being the primary justification 1005). The pivotal trials lasted a median of 18 months for noninferior efficacy evaluations (42). (IQR, 15 to 22 months). As shown in Table 2, the The pivotal trials of fidaxomicin showed noninferi- strength of evidence differed across the drugs. For ex- ority and superiority for effectiveness. Fidaxomicin met ample, approval of ceftolozane–tazobactam was based the primary hypothesis of noninferiority to the standard on 1 trial per indication, because data were pooled of care of on the primary end point of clin- from 2 identical trials each for CUTI and CIAI. Assess- ical cure (decreased diarrhea episodes and clinician

www.annals.org Annals of Internal Medicine 3 Downloaded From: http://annals.org/ by a Boston University Medical Center User on 06/01/2016 MEDICINE AND PUBLIC ISSUES FDA-Approved Antibiotics, 2010-2015

Figure. Company sponsorship of antibiotics that were approved by the FDA from 2010 through 2015.

Peninsula J&J Cerexa Cerexa, wholly owned by Forest Labs Actavis Ceftaroline (TAK-599, PPI-0903) 2004 2010

Optimer Cubist Merck Fidaxomicin (OPT-80, PAR-101) 2003 2011

J&J (Tibotec and Janssen Pharmaceuticals) Bedaquiline (TMC207, R207910) 2006 2012

(Merger) Versicor Vicuron Pfizer Durata Actavis Dalbavancin (BI397) Blosearch 2000 2014 Italia

Dong A Pharmaceuticals (Korea) Licensed by Trius Cubist Merck Tedizolid (TR701) Oral: 2007 IV: 2009 2014 Voluntary Clinical Hold Eli Lilly InterMune Targanta The Medicines Co. Oritavancin (LY333328) 1996 2014

Calixa Cubist Merck Cetolozane– tazobactam (CXA-201, FR264205) 2009 2011

Ceftazidime– Novexel SA AstraZeneca Cerexa Actavis avibactam (NXL104, AVE1330A) 2008 2015

Small or midsized company Large company IND application filed Drug received FDA approval

Company sponsorship timelines and key milestones related to FDA approval are shown. The information in parentheses below each antibiotic is the name of the drug while under development. FDA = U.S. Food and Drug Administration; IND = investigational new drug; IV = intravenous; J&J = Johnson & Johnson.

judgment of no need for further antibiotic therapy) at microbiological success. Superiority was driven by the the end of treatment, on the basis of a 10% margin. It surrogate end point of negative urine cultures in the also demonstrated superiority to the active comparator subgroups of patients with levofloxacin-resistant organ- in 2 studies for the secondary exploratory end point of isms. There were no significant differences between global cure rate—the number of participants in each ceftolozane–tazobactam and levofloxacin in the direct treatment group who were considered cured and did patient outcomes of symptoms of urinary tract infec- not have a recurrence of diarrhea within 21 days after tion, adverse effects, or deaths, even in the subgroup the last dose. However, for patients with C difficile–as- with levofloxacin resistance (43). Both ceftolozane– sociated diarrhea due to the epidemic BI/NAP1/027 tazobactam and ceftazidime–avibactam demonstrated strain, fidaxomicin did not demonstrate superiority in decreased efficacy compared with older control agents global cure. in patients with baseline renal insufficiency. The single trial of ceftolozane–tazobactam in CUTI Bedaquiline was the only approved antibiotic in was designed with a noninferiority hypothesis but our study that was tested solely via a superiority hy- showed superiority compared with the control drug pothesis. A surrogate end point of sputum clearance levofloxacin on the composite outcome of clinical and was used in the single pivotal trial (41), and bedaquiline

4 Annals of Internal Medicine www.annals.org Downloaded From: http://annals.org/ by a Boston University Medical Center User on 06/01/2016 FDA-Approved Antibiotics, 2010-2015 MEDICINE AND PUBLIC ISSUES

Table 2. Characteristics of Pivotal Trials Used to Support FDA Approval of Antibiotics, 2010–2015

Drug and Trial Indication Comparator End Point Analysis Population Hypothesis Name Drug Absolute Risk Patients Who Patients in Reduction (95% CI) Received Drug, Comparator n Group, n Ceftaroline P903-08 CABP Clinical cure at MITTE: 6.2% (–0.2% MITTE: 291 MITTE: 300 Noninferiority test-of-cure* to 12.5%) CE: 224 CE: 234 (–10%) CE: 8.4% (1.4% to 15.4%) P903-09 CABP Ceftriaxone Clinical cure at MITTE: 5.9% (–1.0% MITTE: 284 MITTE: 269 Noninferiority test-of-cure* to 12.8%) CE: 232 CE: 214 (–10%) CE: 5.2% (–2.2% to 12.8%) P903-06 ABSSSI Vancomycin + Clinical cure at MITT: 1.0% (–4.2% to MITT: 351 MITT: 347 Noninferiority test-of-cure† 6.2%) CE: 316 CE: 347 (–10%) CE: –2.2% (–6.6% to 2.1%) P903-07 ABSSSI Vancomycin + Clinical cure at MITT: 0.1% (–4.4% to MITT: 342‡ MITT: 338‡ Noninferiority aztreonam test-of-cure† 4.5%) CE: 294‡ CE: 292‡ (–10%) CE: –0.4% (–5.8% to 5.0%) Fidaxomicin 101.1.C.003 CDAD Vancomycin Clinical cure at MITT: 4.2% (–1.4% to MITT: 289 MITT: 307 Noninferiority end-of-treatment§ 9.7%) (–10%) Global cure (cure MITT: 10.2% (2.8% to Superiority (0%) response with no 17.5) recurrence through poststudy visit) 101.1.C.004 CDAD Vancomycin Clinical cure at MITT: 0.2% (–5.9% to MITT: 253 MITT: 256 Noninferiority end-of-treatment§ 6.4%) (–10%) Global cure (cure MITT: 13.4% (5.4 to Superiority (0%) response with no 21.1) recurrence through post-study visit) Bedaquiline C208 stage Pulmonary TB Placebo with Time to sputum culture Culture conversion MITT: 21 MITT: 23 Exploratory 1 caused by background conversion (2 rates to MITT: MDR-TB regimen consecutive negative Week 8: 38.9% cultures from sputa (12.3% to 63.1%) collected at least 25 d Week 24: 14.8% apart) (–11.9% to 41.9%) Final treatment success: 4.6% (–25.5% to 34.1%) C208 stage Pulmonary TB Placebo with Time to sputum culture MITT: median: 83 d MITT: 79 MITT: 81 Superiority 2 caused by background conversion (2 (56 to 97 d) based on MDR-TB regimen consecutive negative Placebo: median, surrogate end cultures from sputa 125 d (98 to point collected at least 25 d 168 d) apart) Dalbavancin DUR001-301 ABSSSI Vancomycin Early response at 48–72 ITT: 1.5% (–4.6% to ITT: 288 ITT: 285 Noninferiority or h (spread cessation, 7.9%) (–10%) absence of fever) Reduction in lesion area ITT: –1% (–5.7% to from baseline at 4.0%) 48–72 h DUR001-302 ABSSSI Vancomycin Early response at 48–72 ITT: –1.5% (–7.4% to ITT: 371 ITT: 368 Noninferiority or linezolid h (spread cessation, 4.6%) (–10%) absence of fever) Reduction in lesion area ITT: 1.7% (–3.2% to from baseline at 6.7%) 48–72 h Tedizolid TR701-112 ABSSSI Linezolid Early clinical response ITT: 0.1% (–6.1% to ITT: 332 ITT: 335 Noninferiority (spread cessation) at 6.2%) (–10%) 48–72 h ≥20% reduction in ITT: 1.9% (–4.5% to primary lesion with no 8.3%) fever TR701-113 ABSSSI Linezolid Early clinical response ITT: 2.6% (–3.0% to ITT: 332 ITT: 334 Noninferiority (≥20% reduction in 8.2%) (–10%) primary lesion) at 48–72 h Oritavancin SOLO1 ABSSSI Vancomycin Clinical response MITT: 3.7% (–1.4% to MITT: 473 MITT: 481 Noninferiority (spread cessation, no 8.7%) (–10%) fever, no rescue antibiotic) ≥20% reduction in lesion MITT: 3.94% (–0.59% to 8.47%) SOLO2 ABSSSI Vancomycin Clinical response MITT: –2.8% (–7.5% MITT: 503 MITT: 502 Noninferiority (spread cessation, no to 2.0%) (–10%) fever, no rescue antibiotic) ≥20% reduction in lesion MITT: 0.6% (–3.7% to 5.0%) Continued on following page www.annals.org Annals of Internal Medicine 5 Downloaded From: http://annals.org/ by a Boston University Medical Center User on 06/01/2016 MEDICINE AND PUBLIC ISSUES FDA-Approved Antibiotics, 2010-2015

Table 2—Continued

Drug and Trial Indication Comparator End Point Analysis Population Hypothesis Name Drug Absolute Risk Patients Who Patients in Reduction (95% CI) Received Drug, Comparator n Group, n Ceftolozane– tazobactam CXA-CUTI- CUTI Levofloxacin Composite clinical and Microbiological Microbiological Microbiological Noninferiority 10-04 and microbiological cure MITT: 8.5% (2.31% MITT: 398 MITT: 402 (–10%) 10-05 at test-of-cure to 14.57%) (investigator judgment that symptoms had resolved and microbiological eradication of the causative pathogen) CXA-CIAI- CIAI Clinical response at Microbiological ITT: Microbiological Microbiological Noninferiority 10-08 and test-of-cure† –4.6% (–9.4% to ITT: 389 ITT: 417 (–10%) 10-09 0.1%) Ceftazidime– avibactam NXL104/ CUTI when – Microbiological ME: –1.1% (–27.2% to ME: 27 ME: 35 No prespecified 2001 limited cilastatin response (reduction of 25.0%) hypotheses, or no the baseline but results treatment uropathogen at entry interpreted at options are from >105 CFU/mL to noninferiority available <104 CFU/mL) Clinical and Microbiological Microbiological Microbiological microbiological MITT: 12% (–9.1% MITT: 46 MITT: 49 response (cure + to 31.7%) eradication) NXL104/ CIAI, in Meropenem Clinical response (clinical ME: –2.2% (–20.4% to ME: 68 ME: 76 No prespecified 2002 combination cure: complete 12.2%) Microbiological Microbiological hypotheses, with resolution or Microbiological MITT: 85 MITT: 89 but results significant MITT: –6.4% interpreted as when improvement in (–18.0% to 5.2%) noninferiority limited or symptoms of index no infection with no treatment further therapy options are needed; eradication available presumed with favorable clinical response) ABSSSI = acute bacterial skin and skin-structure infection; CABP = community-acquired bacterial pneumonia; CDAD = Clostridium difficile–associ- ated diarrhea; CE = clinically evaluable; CFU = colony-forming units; CIAI = complicated intra-abdominal infection; CUTI = complicated urinary tract infection; FDA = U.S. Food and Drug Administration; ITT = intention to treat; MDR-TB = multidrug-resistant tuberculosis; ME = microbiologically evaluable; MITT = modified intention to treat; MITTE = modified intention to treat efficacy; TB = tuberculosis. * Total resolution of symptoms, or improvement with absence of fever such that no additional antibiotics necessary. † Total resolution of all signs and symptoms, or improvement such that no additional antibiotics necessary. ‡ Data from reference 40. § No further therapy 2 d after completion; 3 or fewer unformed stools for 2 consecutive d and remained well before discontinuation; or marked reduction in number of unformed stools, with residual abdominal discomfort deemed as recovering bowel, provided no further therapy required.

showed 79% clearance versus 58% at 24 weeks in the patient mortality or direct measures of patient disability standard-of-care group, although the difference was as primary end points. not significant at later time points. However, incidence of death, generally from tuberculosis, increased 5-fold Regulatory Review Characteristics among patients randomly assigned to the experimental Each of the 8 antibiotics received at least 1 expe- group compared with those assigned to receive stan- dited drug development or FDA review designation. dard treatment (45). All 8 were fast-tracked, and 7 received priority review. Most of the primary and key secondary end points For the most recent 5 antibiotics, the fast-track status examined in the trials were clinical “cures” and “re- and priority review were conferred on the basis of the sponses” based on subjective clinician judgments of drugs receiving the qualified infectious disease prod- unclearly defined composites of signs, symptoms, and uct designation. Bedaquiline also received accelerated laboratory values or radiologic results. For example, in approval. Four of the drugs—dalbavancin, tedizolid, ori- the case of fidaxomicin, a component of the end point tavancin, and ceftolozane/tazobactam—were awarded of interest was clinician judgments on need for addi- additional market exclusivity through the GAIN Act. tional antibiotics for C difficile (46). Exceptions included the bedaquiline trials (sputum clearance surrogate); One drug, bedaquiline, was awarded orphan drug CUTI studies that used a composite of “clinical” and status and earned its manufacturer a priority review microbiological outcomes of urine cultures; and acute voucher—an incentive created to reward sponsors for bacterial skin and skin-structure infection trials for dal- developing drugs to treat neglected diseases. bavancin, tedizolid, and oritavancin (the well-defined clinician-reported outcome of ≥20% reduction in lesion size in addition to clinical cure or response). None used

6 Annals of Internal Medicine www.annals.org Downloaded From: http://annals.org/ by a Boston University Medical Center User on 06/01/2016 FDA-Approved Antibiotics, 2010-2015 MEDICINE AND PUBLIC ISSUES

Table 3. Dose, Duration, and Cost of Antibiotic Drugs and Trial Comparators

New Antibiotic Comparator Cost Ratio

Drug Dose and Cost Range, $* Drug Dose and Duration Cost Range, $* Duration Ceftaroline CABP: 600 mg CABP: CABP: ceftriaxone CABP:1gof CABP: 9.00–329.35 CABP: 185:1 to every 12 h for 1666.30–2332.82 ceftriaxone once daily 7:1 5–7 d for 5–7 d ABSSSI: 600 mg ABSSSI: ABSSSI: vancomycin + ABSSSI:1gof ABSSSI: 470.10–1681.68 ABSSSI: 4:1 to every 12 h for 1666.30–4665.64 aztreonam vancomycin twice 3:1 5–14 d daily and1gof aztreonam twice daily for 5–14 d Fidaxomicin 200 mg twice 3969.20 Vancomycin† 125-mg capsule 4 times 1252.00–1392.00 3:1 daily for 10 d daily for 10 d Bedaquiline 400 mg daily for 36 000.12 Placebo (both groups –‡ –‡ –‡ 2 wk, then 200 received a mg 3 background times/wk for multidrug anti–TB 22 wk treatment regimen) Dalbavancin 1 dose of 1000 5364.00 Vancomycin or 1 g of vancomycin twice Vancomycin: Vancomycin: mg, then 500 linezolid daily for 3–14 d, with 44.82–574.56 120:1 to 9:1 mg 8 d later optional switch to 600 Linezolid: 2938.72 Linezolid: 2:1 mg of linezolid twice daily for 8 d Tedizolid 200 mg once Oral: 2124 Linezolid 600 mg twice a day for 3673.40 Oral: 0.5:1 daily for 6 d IV: 1692 10 d IV: 0.5:1 Oritavancin 1200 mg dose 3480.00 Vancomycin 1 g every 12 h for 7–10 104.58–410.40 33:1 to 9:1 administered d by IV once Ceftolozane– CUTI: 1.5 g CUTI: 2091.60 CUTI: levofloxacin CUTI: 750 mg CUTI: 0.35–0.70 CUTI: 5976:1 to tazobactam every8hfor levofloxacin daily for 2988:1 7d 7d CIAI:1.5 g every CIAI: CIAI: meropenem CIAI:1gofmeropenem CIAI: 154.20–2111.10 CIAI: 8:1 to 2:1 8 h for 4–14 d 1195.20–4183.20 every 8 h for 4–10 d Ceftazidime– CUTI: 2.5 g CUTI: 7182–14 364 CUTI: imipenem– CUTI: 500 mg CUTI: 352.80–1680.00 CUTI: 20:1 to avibactam every8hfor cilastatin imipenem–cilastatin 9:1 7–14 d every 6 h for 7–14 d (optional switch to ciprofloxacin after 4 d) CIAI: 2.5 g every CIAI: 5130–14 364 CIAI: meropenem CIAI:1gofmeropenem CIAI: 192.75–2955.54 CIAI: 27:1 to 8 h for 5–14 d every 8 h for 5–14 d 5:1 + MTZ ABSSSI = acute bacterial skin and skin-structure infection; CABP = community-acquired bacterial pneumonia; CIAI = complicated intra-abdominal infection; CUTI = complicated urinary tract infection; IV = intravenous; MTZ = metronidazole; TB = tuberculosis. * Based on reference 33. † Although the fidaxomicin trials used oral vancomycin (cost shown here), some providers may compound generic IV into oral administration, greatly reducing the cost. ‡ Background multidrug anti-TB regimen varied by individual. Possible drugs included ethionamide, kanamycin, ofloxacin, pyrazinamide, and terizidine (all off-patent).

Postmarket Commitments index drugs (such as warfarin); and assessment of long- and Requirements term outcomes of failure or relapse or death for be- daquiline. Johnson & Johnson was also required to Among the associated postmarket commitments conduct a follow-up trial confirming the efficacy of be- and requirements (Appendix Table 1, available at www daquiline because of its accelerated approval based on .annals.org), the development of bacterial resistance a surrogate end point, but was given until 2022 to com- over 5 years after introduction of the drug to the market plete it. A trial to answer the question of whether the (using in vitro data alone without a requirement for cor- surrogate end point of sputum culture conversion leads relation with patient outcomes) had to be assessed for to direct patient benefits, such as improved survival, all 8 drugs, and tests in pediatric populations were re- had not been initiated as of April 2016, according to quired for all drugs except bedaquiline. Three drugs ClinicalTrials.gov. had additional postmarket requirements intended to clarify safety and efficacy questions: worse outcomes Duration of Treatment and Drug Prices noted for ceftazidime–avibactam compared with the The duration of treatment ranged from a single standard of care among patients with baseline renal dose, in the case of oritavancin, to 24 weeks, in the case impairment; the of oritavancin in of bedaquiline. Prices (Table 3 and Appendix Table 2, patients with severe hepatic or renal impairment, par- available at www.annals.org) ranged from $1195 to ticularly during coadministration of narrow therapeutic $4183 (4 to 14 days of ceftolozane–tazobactam for

www.annals.org Annals of Internal Medicine 7 Downloaded From: http://annals.org/ by a Boston University Medical Center User on 06/01/2016 MEDICINE AND PUBLIC ISSUES FDA-Approved Antibiotics, 2010-2015

CIAI) to $36 000 (24 weeks of bedaquiline). With the approval on the basis of a single pivotal trial occurred exception of tedizolid, these prices are much higher about one third of the time in a recent review. Contin- than those of the comparator drugs—usually generics— ued monitoring and evidence generation are still used in the pivotal trials (33). needed for these antibiotics to ensure demonstration of their efficacy in relevant populations and resistance profiles related to patient outcomes moving forward DISCUSSION (49). We found that most new antibiotics were additions Despite unclear evidence of additional benefit, to existing drug classes, and half were for the same most of these drugs have been priced at a premium. indication. Recently added incentives for antibiotic de- Yet, none of these antibiotics have attained substantial velopment have not yet led to new products with im- sales since their approval. Ceftaroline, for example, re- proved outcomes in patients with disease due to critical corded $13.1 million in sales in 2013 (54). One reason resistant pathogens at the time of approval, such as could be the poor clinical evidence supporting their ESKAPE pathogens (35). Although the Infectious Dis- use; private payers have sometimes resisted reimburs- eases Society of America's goal of 10 new antibiotics ing high-priced new drugs without solid underlying ev- approved by 2020 is likely to be met (20, 35, 38), re- idence of additional benefits over available lower- cently approved antibiotics have generally been lack- priced therapies (even if the FDA does not require such ing in biological innovation or public health importance evidence for approval). For example, the Centers for (47). Medicare & Medicaid Services refused to grant addi- One major exception was bedaquiline, which was tional reimbursement to dalbavancin under the new developed to treat a pressing global public health pri- technology add-on payment program, which is de- ority in multidrug-resistant tuberculosis. Yet, even for signed to support timely access to important but po- bedaquiline, the clinical trials results show increased tentially costly new therapies, owing to the absence of mortality and its initial impact has been limited owing evidence demonstrating superiority or that improved to its lack of availability and lack of data on its use (48). convenience affected patient-centered outcomes (16). Postmarket commitments for this product remain in Our data show that the FDA is efficiently approving progress, a finding consistent with current limitations in new antibiotics. The FDA review time was shorter than our ability to conduct timely postmarket oversight of for small-molecule anti-infective drugs approved in drugs approved via expedited pathways (49). previous years (55). Antibiotic clinical trials are also We also found important deficiencies in the clinical speedy. The length of the pivotal clinical trials—which trials leading to approval of these new antibiotic prod- are supposed to be the longest and most detailed eval- ucts. First, because most pivotal trial designs were pri- uation of a drug—was consistent with or was even marily noninferiority trials, the antibiotics were not stud- shorter than that for other drugs (56). Finally, the num- ied to evaluate whether they have substantial benefits ber of patients enrolled in antibiotic pivotal trials histor- in efficacy over what is currently available. None of the ically has been smaller compared with other therapeu- drugs demonstrated superior outcomes on patient tic areas (56). These data undermine the claim that survival or disability in their pivotal trials despite prom- clinical development of antibiotics is unreasonably bur- ising in vitro, animal, and pharmacokinetic data. For densome (57, 58). example, the apparent superiority of ceftolozane– Despite the ease of testing and approving new an- tazobactam was based on a surrogate end point of tibiotics, research and development is still largely be- negative urine cultures, and bedaquiline worsened sur- ing driven outside of the major pharmaceutical manu- vival despite positive results on a surrogate end point. facturers. Financial incentives tailored to small or Second, none of the trials evaluated direct patient midsized companies may therefore be most effective in outcomes as primary end points. Clinical cure and re- leading to new innovation. Some examples that have sponse end points examined in these trials were based been offered include transferrable tax credits, gener- on clinician judgments of a composite of signs, symp- ous patent buyouts, and prizes (59). Such financial in- toms, or laboratory tests, sometimes with no clear def- centives could also be tailored to ensure that they ap- inition of what was measured or how clinicians were to ply only to novel therapies directed at infections of gauge success (2). In the trials of dalbavancin, oritavan- particular public health importance. The upfront invest- cin, and tedizolid, the primary end point of clinical re- ment needed in the field of antibiotics also may not be sponse was cessation of spread of the baseline lesion, as high as expected; indeed, a recent model of antibi- absence of fever, and no rescue antibiotic , otic drug development assumed longer review times none of which are direct measures of patient survival or and longer clinical development times than we report disability (50–52). here (59). Finally, some drugs did not have confirmatory evi- Our study has limitations. First, future research may dence from a second independent trial or did not have show that these new antibiotics could offer substantial any confirmatory trials (as was the case for ceftazidime– benefits to patients—for example, in terms of dosing avibactam). The FDA has traditionally preferred 2 trials convenience facilitating earlier discharge from per indication because the results of any single trial hospitals—even though such data were lacking at the “may be subject to unanticipated, undetected system- time of approval. Second, new drugs from older classes atic biases” or occur by chance alone (53), although may show superior effectiveness over older drugs in

8 Annals of Internal Medicine www.annals.org Downloaded From: http://annals.org/ by a Boston University Medical Center User on 06/01/2016 FDA-Approved Antibiotics, 2010-2015 MEDICINE AND PUBLIC ISSUES

the same class in specific patient populations. Finally, Current author addresses and author contributions are avail- we obtained the initial U.S. price for each new antibiotic able at www.annals.org. from public sources, as opposed to the manufacturers of the drugs. This does not allow us to adequately ac- count for differences in negotiated rates associated References with public and private payers. 1. U.S. Department of Commerce and Labor. Mortality Statistics, In conclusion, we found that recent antibiotic de- 1900 to 1904. Washington, DC: US Gov Pr Office; 1906. velopment activity has been impressive in terms the 2. Centers for Disease Control and Prevention (CDC). Control of in- quantity of antibiotics developed and approved for fectious diseases. MMWR Morb Mortal Wkly Rep. 1999;48:621-9. marketing, but does not constitute a substantial im- [PMID: 10458535] 3. Laxminarayan R, Matsoso P, Pant S, Brower C, Røttingen JA, provement in terms of quality in clinical practice on pa- Klugman K, et al. Access to effective antimicrobials: a worldwide tient outcomes. A range of regulatory and other incen- challenge. Lancet. 2016;387:168-75. [PMID: 26603918] doi:10 tives have targeted antibiotic development, and the .1016/S0140-6736(15)00474-2 FDA has demonstrated efficiency in approving antibiot- 4. Armstrong GL, Conn LA, Pinner RW. Trends in infectious disease ics. However, many of the drugs in our cohort were mortality in the United States during the 20th century. JAMA. 1999; approved for the same indication, only 1 was first in 281:61-6. [PMID: 9892452] class, and numerous deficiencies were identified in the 5. Roberts RR, Hota B, Ahmad I, Scott RD 2nd, Foster SD, Abbasi F, et al. Hospital and societal costs of antimicrobial-resistant infections clinical trial evidence collected at the time of approval. in a Chicago teaching hospital: implications for antibiotic steward- Only 1 drug was studied in patients with multidrug- ship. Clin Infect Dis. 2009;49:1175-84. [PMID: 19739972] doi:10 resistant disease. As antibiotic innovation continues to .1086/605630 move forward, greater attention needs to be paid to 6. Centers for Disease Control and Prevention. Antibiotic Resistance incentives for developing high-quality new products Threats in the United States, 2013. Atlanta, GA: Centers for Disease with demonstrated superiority to existing products on Control and Prevention; 2013. outcomes in patients with multidrug-resistant disease, 7. World Health Organization. Antimicrobial Resistance: Global Re- port on Surveillance. Geneva: World Health Organization; 2014. replacing the current focus on quantity and presumed 8. Morel CM, Mossialos E. Stoking the antibiotic pipeline. BMJ. 2010; future benefits. 340:c2115. [PMID: 20483950] doi:10.1136/bmj.c2115 9. Spellberg B, Powers JH, Brass EP, Miller LG, Edwards JE Jr. From Program on Regulation, Therapeutics, and Law Trends in antimicrobial drug development: implications for the fu- (PORTAL), Brigham and Women's Hospital, Harvard Medical ture. Clin Infect Dis. 2004;38:1279-86. [PMID: 15127341] School, and School of Law, Boston University, Boston, Massa- 10. Projan SJ. Why is Big Pharma getting out of antibacterial drug chusetts; and George Washington University School of Medi- discovery? Curr Opin Microbiol. 2003;6:427-30. [PMID: 14572532] cine Washington, DC. 11. Coates A, Hu Y, Bax R, Page C. The future challenges facing the development of new antimicrobial drugs. Nat Rev Drug Discov. 2002;1:895-910. [PMID: 12415249] Disclosures: Prof. Outterson reports grants from the European 12. Norrby SR, Nord CE, Finch R; European Society of Clinical Mi- Union—DRIVE-AB and other from Roche-Genentech Anti- crobiology and Infectious Diseases. Lack of development of new an- Infectives Advisory Board and Pure Tech outside the submit- timicrobial drugs: a potential serious threat to public health. Lancet Infect Dis. 2005;5:115-9. [PMID: 15680781] ted work. Dr. Powers reports personal fees from Cardeas, 13. Outterson K, Powers JH, Seoane-Vazquez E, Rodriguez- Contrafect, Gilead, Johnson & Johnson, MedImmune, No- Monguio R, Kesselheim AS. Approval and withdrawal of new antibi- vartis, Otsuka, Pfizer, and Trius outside the submitted work. otics and other antiinfectives in the U.S., 1980-2009. J Law Med Eth- Dr. Kesselheim reports grants from the Greenwall Foundation, ics. 2013;41:688-96. [PMID: 24088160] doi:10.1111/jlme.12079 Harvard Program in Therapeutic Science, U.S. Food and Drug 14. Lewis K. Platforms for antibiotic discovery. Nat Rev Drug Discov. Administration Office of Generic Drugs and Division of Health 2013;12:371-87. [PMID: 23629505] doi:10.1038/nrd3975 Communication, and Laura and John Arnold Foundation out- 15. So AD, Gupta N, Brahmachari SK, Chopra I, Munos B, Nathan C, side the submitted work; further, he is an unpaid member of et al. Towards new business models for R&D for novel antibiotics. the governance board of the DRIVE-AB consortium, which is a Drug Resist Updat. 2011;14:88-94. [PMID: 21439891] doi:10.1016/j venture of the European Innovative Medicines Initiative. Ms. .drup.2011.01.006 Deak has disclosed no conflicts of interest. Disclosures can 16. Outterson K, Powers JH, Daniel GW, McClellan MB. Repairing the broken market for antibiotic innovation. Health Aff (Millwood). also be viewed at www.acponline.org/authors/icmje/Conflict 2015;34:277-85. [PMID: 25646108] doi:10.1377/hlthaff.2014.1003 OfInterestForms.do?msNum=M16-0291. 17. The White House. National Strategy for Combating Antibiotic- Resistant Bacteria. Washington, DC: US Gov Pr Office; 2014. 18. Centers for Disease Control and Prevention. Antibiotic resistance Financial Support: By the Greenwall Faculty Scholars in Bio- solutions initiative 2015. 2015. Accessed at www.cdc.gov/drug ethics Program, the Laura and John Arnold Foundation, and resistance/solutions-initiative/index.html on 13 October 2015. the Harvard Program in Therapeutic Science (Dr. Kesselheim). 19. World Health Organization. WHO Global Strategy for Contain- Prof. Outterson is a partner in DRIVE-AB, which is funded by ment of Antimicrobial Resistance. Geneva: World Health Organiza- the European Union's Innovative Medicines Initiative. tion; 2001. 20. Infectious Diseases Society of America. The 10 x ‘20 Initiative: pursuing a global commitment to develop 10 new antibacterial Requests for Single Reprints: Aaron S. Kesselheim, MD, JD, drugs by 2020. Clin Infect Dis. 2010;50:1081-3. [PMID: 20214473] MPH, Program on Regulation, Therapeutics, and Law doi:10.1086/652237 (PORTAL), Brigham and Women's Hospital and Harvard Med- 21. Clift C, Gopinathan U, Morel C, Outterson K, Røttingen J, So A, ical School, 1620 Tremont Street, Suite 3030, Boston, Massa- eds; Chatham House Working Group on New Antibiotic Business chusetts 02120; e-mail, [email protected]. Models. Towards a New Global Business Model for Antibiotics:

www.annals.org Annals of Internal Medicine 9 Downloaded From: http://annals.org/ by a Boston University Medical Center User on 06/01/2016 MEDICINE AND PUBLIC ISSUES FDA-Approved Antibiotics, 2010-2015

Delinking Revenues from Sales. London: The Royal Institute of Inter- treatment of patients with complicated skin and skin structure infec- national Affairs; 2015. tions. J Antimicrob Chemother. 2010;65 Suppl 4:iv53-iv65. [PMID: 22. Food and Drug Administration Safety and Innovation Act of 2013 21115455] doi:10.1093/jac/dkq255 § 3187 (2013). 41. Diacon AH, Pym A, Grobusch MP, de los Rios JM, Gotuzzo E, 23. 21st Century Cures Act, H.R. 6 (2015). Vasilyeva I, et al; TMC207-C208 Study Group. Multidrug-resistant 24. Woodcock J. Three encouraging steps towards new antibiotics. tuberculosis and culture conversion with bedaquiline. N Engl J Med. FDA Voice Blog. 23 September 2014. Accessed at http://blogs.fda 2014;371:723-32. [PMID: 25140958] doi:10.1056/NEJMoa1313865 .gov/fdavoice/index.php/2014/09/three-encouraging-steps-towards 42. International Conference on Harmonisation of Technical Re- -new-antibiotics on 26 April 2016. quirements for Registration of Pharmaceuticals for Human Use. ICH 25. U.S. Food and Drug Administration. CDER new molecular entity harmonised tripartite guideline: choice of control group and related (NME) & new BLA calendar year approvals as of December 31, 2010. issues in clinical trials E10. 2000. Accessed at www.ich.org/fileadmin 2010. Accessed at www.fda.gov/downloads/Drugs/Development /Public_Web_Site/ICH_Products/Guidelines/Efficacy/E10/Step4/E10 ApprovalProcess/HowDrugsareDevelopedandApproved/Drugand _Guideline.pdf on 26 April 2016. BiologicApprovalReports/UCM242677.pdf on 26 April 2016. 43. U.S. Food and Drug Administration. Statistical Review, Ceftolo- 26. U.S. Food and Drug Administration. Novel new drugs summary zane/Tazobactam (Zerbaxa). Silver Spring, MD: U.S. Food and Drug 2012. 2013. Accessed at www.fda.gov/downloads/Drugs/Develop Administration; 2014. mentApprovalProcess/DrugInnovation/UCM337830.pdf on 26 April 44. 21 C.F.R. 314.500 (2015). 2016. 45. Cox E, Laessig K. FDA approval of bedaquiline—the benefit-risk 27. U.S. Food and Drug Administration. Novel new drugs 2011. balance for drug-resistant tuberculosis. N Engl J Med. 2014;371: 2012. Accessed at www.fda.gov/downloads/Drugs/Development 689-91. [PMID: 25140952] doi:10.1056/NEJMp1314385 ApprovalProcess/DrugInnovation/ucm293663.pdf on 26 April 46. U.S. Food and Drug Administration. Medical Review: Dificid 2016. (Fidaxomicin). Silver Spring, MD: U.S. Food and Drug Administra- 28. U.S. Food and Drug Administration. Novel new drugs 2014 sum- tion; 2011. mary. 2015. Accessed at www.fda.gov/downloads/Drugs/Develop 47. Doshi P. Speeding new antibiotics to market: a fake fix? BMJ. mentApprovalProcess/DrugInnovation/UCM430299.pdf on 26 April 2015;350:h1453. [PMID: 25814536] doi:10.1136/bmj.h1453 2016. 48. Brigden G, Hewison C, Varaine F. New developments in the 29. U.S. Food and Drug Administration. Novel new drugs 2013 sum- treatment of drug-resistant tuberculosis: clinical utility of bedaquiline mary. 2014. Accessed at www.fda.gov/downloads/Drugs/Develop and delamanid. Infect Drug Resist. 2015;8:367-78. [PMID: mentApprovalProcess/DrugInnovation/UCM381803.pdf on 26 April 26586956] doi:10.2147/IDR.S68351 2016. 49. U.S. Government Accountability Office. Drug Safety: FDA Expe- 30. U.S. Food and Drug Administration. New Molecular Entity and dites Many Applications, but Data for Postapproval Oversight Need New Therapeutic Biological Product Approvals for 2015. Silver Improvement. Washington, DC: U.S. Government Accountability Of- Spring, MD: U.S. Food and Drug Administration; 2015. Accessed at fice; 2015. www.fda.gov/Drugs/DevelopmentApprovalProcess/DrugInnovation 50. Prokocimer P, De Anda C, Fang E, Mehra P, Das A. Tedizolid /ucm430302.htm on 26 April 2016. phosphate vs linezolid for treatment of acute bacterial skin and skin 31. U.S. Food and Drug Administration. Postmarket requirements structure infections: the ESTABLISH-1 randomized trial. JAMA. 2013; and commitments. 2013. Accessed at www.accessdata.fda.gov 309:559-69. [PMID: 23403680] doi:10.1001/jama.2013.241 /scripts/cder/pmc on 26 April 2016. 51. Corey GR, Good S, Jiang H, Moeck G, Wikler M, Green S, et al; 32. U.S. Food and Drug Administration. Orange Book: Approved SOLO II Investigators. Single-dose oritavancin versus 7-10 days of Drug Products with Therapeutic Equivalence Evaluations. 2013. Ac- vancomycin in the treatment of gram-positive acute bacterial skin cessed at www.accessdata.fda.gov/scripts/cder/ob/default.cfm on 4 April 2016. and skin structure infections: the SOLO II noninferiority study. Clin 33. Red Book Online [online database]. Greenwood Village, CO: Infect Dis. 2015;60:254-62. [PMID: 25294250] doi:10.1093 Truven Health Analytics. Accessed at http://sites.truvenhealth.com /cid/ciu778 /redbook/index.html on 26 April 2016. 52. Boucher HW, Wilcox M, Talbot GH, Puttagunta S, Das AF, Dunne 34. Rice LB. Federal funding for the study of antimicrobial resistance MW. Once-weekly dalbavancin versus daily conventional therapy for in nosocomial pathogens: no ESKAPE [Editorial]. J Infect Dis. 2008; skin infection. N Engl J Med. 2014;370:2169-79. [PMID: 24897082] 197:1079-81. [PMID: 18419525] doi:10.1086/533452 doi:10.1056/NEJMoa1310480 35. Boucher HW, Talbot GH, Bradley JS, Edwards JE, Gilbert D, Rice 53. U.S. Food and Drug Administration. Guidance on Providing Clin- LB, et al. Bad bugs, no drugs: no ESKAPE! An update from the Infec- ical Evidence of Effectiveness for Human Drugs and Biologics. Silver tious Diseases Society of America. Clin Infect Dis. 2009;48:1-12. Spring, MD: U.S. Food and Drug Administration; 1998:4-5. [PMID: 19035777] doi:10.1086/595011 54. Actavis + Forest Laboratories. Forest Laboratories, Inc. reports 36. Prasad P, Sun J, Danner RL, Natanson C. Excess deaths associ- fiscal year fourth quarter 2013 earnings per share of $0.17 including ated with tigecycline after approval based on noninferiority trials. $0.08 per share of acquisition amortization [press release]. 23 April Clin Infect Dis. 2012;54:1699-709. [PMID: 22467668] doi:10.1093 2013. Accessed at http://investor.frx.com/press-release/corporate /cid/cis270 -news/forest-laboratories-inc-reports-fiscal-year-fourth-quarter-2013 37. U.S. Food and Drug Administration. Doribax (doripenem): drug -earning on 13 October 2015. safety communication—risk when used to treat pneumonia on 55. Reichert JM. Trends in development and approval times for new ventilated patients. 2014. Accessed at www.fda.gov/Safety/Med therapeutics in the United States. Nat Rev Drug Discov. 2003;2:695- Watch/SafetyInformation/SafetyAlertsforHumanMedicalProducts 702. [PMID: 12951576] /ucm388328.htm on 4 April 2016. 56. DiMasi JA, Hansen RW, Grabowski HG. The price of innovation: 38. Bassetti M, Merelli M, Temperoni C, Astilean A. New antibiotics new estimates of drug development costs. J Health Econ. 2003;22: for bad bugs: where are we? Ann Clin Microbiol Antimicrob. 2013; 151-85. [PMID: 12606142] 12:22. [PMID: 23984642] doi:10.1186/1476-0711-12-22 57. Rex JH, Goldberger M, Eisenstein BI, Harney C. The evolution of 39. Kotz J. Targeting tuberculosis. Nat Chem Biol. 2005. Accessed the regulatory framework for antibacterial agents. Ann N Y Acad Sci. at www.nature.com/nchembio/journal/vaop/nprelaunch/full/nchem 2014;1323:11-21. [PMID: 24797794] doi:10.1111/nyas.12441 bio002.html on 26 April 2016. 58. Alemayehu D, Quinn J, Cook J, Kunkel M, Knirsch CA. A para- 40. Wilcox MH, Corey GR, Talbot GH, Thye D, Friedland D, Baculik digm shift in drug development for treatment of rare multidrug- T; CANVAS 2 investigators. CANVAS 2: the second phase III, ran- resistant gram-negative pathogens. Clin Infect Dis. 2012;55:562-7. domized, double-blind study evaluating for the [PMID: 22610933] doi:10.1093/cid/cis503

10 Annals of Internal Medicine www.annals.org Downloaded From: http://annals.org/ by a Boston University Medical Center User on 06/01/2016 FDA-Approved Antibiotics, 2010-2015 MEDICINE AND PUBLIC ISSUES

59. Sertkaya A, Eyraud J, Birkenbach A, Franz C, Ackerley N, Over- 60. U.S. Food and Drug Administration. Guidance for Industry: Ex- ton V, et al. Analytical Framework for Examining the Value of Anti- pedited Programs for Serious Conditions—Drugs and Biologics. Sil- bacterial Products. Washington, DC: U.S. Department of Health and ver Spring, MD: U.S. Food and Drug Administration; 2014. Human Services; 2014. 61. The Orphan Drug Act of 1983 (1983).

www.annals.org Annals of Internal Medicine 11 Downloaded From: http://annals.org/ by a Boston University Medical Center User on 06/01/2016 Current Author Addresses: Ms. Deak and Dr. Kesselheim: clinical benefit on how patients feel, function, or survive Program on Regulation, Therapeutics, and Law (PORTAL), (60). Brigham and Women's Hospital and Harvard Medical School, Breakthrough therapy offers increased resources 1620 Tremont Street, Suite 3030, Boston, MA 02120. and cross-disciplinary attention within the FDA that are Prof. Outterson: School of Law, Boston University, 765 Com- monwealth Avenue, Boston, MA 02215. intended to speed development (60). Dr. Powers: George Washington University School of Medi- Fast track affords the sponsor frequent interactions cine, 2300 Eye Street, NW, Washington, DC 20037. with the FDA review team and the promise of more efficient review, if the FDA determines that the product Author Contributions: Conception and design: D. Deak, K. for life-threatening disease may be effective and may Outterson, J.H. Powers, A.S. Kesselheim. have added benefits over available therapies after pre- Analysis and interpretation of the data: D. Deak, K. Outterson, liminary evaluation of the clinical data (60). J.H. Powers, A.S. Kesselheim. Orphan drug status provides a sponsor with tax Drafting of the article: D. Deak, J.H. Powers. breaks, access to special grant funding, waiver of reg- Critical revision of the article for important intellectual con- ulatory fees, and 7 years of market exclusivity after ap- tent: D. Deak, K. Outterson, J.H. Powers, A.S. Kesselheim. Final approval of the article: D. Deak, K. Outterson, J.H. Pow- proval (61). ers, A.S. Kesselheim. Priority review guarantees initial FDA review within Statistical expertise: D. Deak, J.H. Powers. 6 months instead of the standard 10-month deadline Obtaining of funding: A.S. Kesselheim. (60). Collection and assembly of data: D. Deak, K. Outterson. Qualified infectious disease product designation, available since 2012, is made before any clinical data are available. It provides incentives that include the APPENDIX:DEFINITIONS OF FDA-EXPEDITED prospect of a shorter preapproval development period, DEVELOPMENT OR REVIEW PROGRAMS automatic priority review, and a 5-year extension of ex- Accelerated approval allows approval to be based clusivity after approval. Unlike the standard fast track, on a surrogate end point or an intermediate clinical the new drug does not need to have promise of added end point that is reasonably likely to predict a drug's benefits (22).

www.annals.org Annals of Internal Medicine Downloaded From: http://annals.org/ by a Boston University Medical Center User on 06/01/2016 Appendix Table 1. Postmarket Commitments and Requirements as of December 2015*

Drug PMR/Commitment (Status†) Ceftaroline fosamil 1. Perform a trial in pediatric patients being treated concomitantly with antibacterial agent(s) to evaluate single-dose pharmacokinetic parameters and assess safety of Teflaro (ceftaroline fosamil) in all pediatric age groups. Required under PREA (fulfilled) 2. Perform a randomized comparison of Teflaro (ceftaroline fosamil) and comparator in pediatric patients with CABP utilizing an enrichment strategy for enrollment of patients with MRSA. Pediatric patients aged <17 y with CABP must be enrolled, with a minimum of 150 patients receiving Teflaro (ceftaroline fosamil). Required under PREA (submitted) 3. Perform a randomized comparison of Teflaro (ceftaroline fosamil) and comparator in pediatric population with ABSSSI, including patients with infection suspected or demonstrated to be caused by MRSA. Pediatric patients aged <17 y with ABSSSI must be enrolled, with a minimum of 150 patients receiving Teflaro (ceftaroline fosamil). Required under PREA (submitted) 4. Perform a trial assessing the CSF concentration profile of Teflaro (ceftaroline fosamil) in infants aged <2 mo. A minimum of 12 infants aged <2 mo receiving antibacterials for treatment of late-onset neonatal sepsis must be studied. Required under PREA (pending) 5. Perform a randomized comparison of Teflaro (ceftaroline fosamil) and comparator in infants aged <2 mo with ABSSSI and CABP, including patients with infections suspected or demonstrated to be caused by MRSA. Required under PREA (pending) 6. Conduct a prospective study over a 5-y period after introduction of Teflaro (ceftaroline fosamil) to the market to determine whether decreased susceptibility to Teflaro (ceftaroline fosamil) is occurring in the target bacteria included in the Indications section of the approved Teflaro (ceftaroline fosamil) package insert. Provide a detailed protocol describing the study to the FDA for review and comment before commencing the study. Required under FDAAA (ongoing) Fidaxomicin 1. Conduct a prospective clinical trial of 10 d of Dificid (fidaxomicin) in at least 32 pediatric patients (aged 6 mo to <18 y) with Clostridium difficile–associated diarrhea to evaluate the safety and pharmacokinetics (including serum and fecal concentrations) of Dificid (fidaxomicin). Required under PREA (fulfilled) 2. Conduct a prospective, randomized clinical trial to demonstrate safety and effectiveness of Dificid (fidaxomicin) compared with vancomycin in pediatric patients (aged 6 mo to <18 y) with C difficile–associated diarrhea. Required under PREA (pending) 3. Conduct a prospective study over a 5-y period after introduction of Dificid (fidaxomicin) to the market to determine whether decreased susceptibility to Dificid (fidaxomicin) is occurring in C difficile. Provide a detailed protocol describing the study to the FDA for review and comment before commencing the study. Required under FDAAA (ongoing) 4. Conduct a prospective, randomized, comparative trial to demonstrate the efficacy of Dificid (fidaxomicin) in the treatment of patients with multiple recurrences of C difficile associated diarrhea (pending) Bedaquiline 1. Conduct a confirmatory randomized, double-blind, placebo-controlled, multicenter, phase 3 trial in persons with sputum smear–positive pulmonary MDR-TB. This trial should assess long-term outcomes of failure or relapse or death ≥6 mo after all MDR-TB treatment is completed. Required under accelerated approval (ongoing) [Note: Described as “ongoing” in the FDA database, but not listed as under way on ClinicalTrials.gov] 2. Develop a patient registry for bedaquiline-treated patients to assess incidence rates of serious adverse events, including death. Required under FDAAA (pending) 3. To inform PMR 5, conduct a study to define the quality control ranges of bedaquiline for MDR-TB isolates using standard proportion methods. Required under FDAAA (fulfilled) 4. To inform PMR 5, conduct a study to define the quality control ranges of bedaquiline for MDR-TB isolates using MIC methods. Required under FDAAA (fulfilled) 5. Conduct a prospective in vitro study over a 5-y period after introduction of Sirturo (bedaquiline) to the market to determine MICs of MDR-TB isolates to bedaquiline for the first 5 y from marketing. Report interpretation of these MICs once additional quality control testing methods are developed as noted in the required postmarketing studies for PMRs 3 and 4. Provide a detailed protocol describing the study to the FDA for review and comment before commencing the study. Required under FDAAA (pending) 6. Conduct an in vitro study to characterize the potential of bedaquiline and M2 as a substrate, inhibitor or inducer of the OATP1B1 and OATP1B3 drug transporters. Required under FDAAA (fulfilled) 8. Submit final study report and electronic data for Study C208 Stage II (fulfilled) 9. Submit final study report and electronic data for Study C209 (fulfilled) Dalbavancin 1. Conduct a single-dose pharmacokinetic study in children aged 3 mo to <12 y. Required under PREA (ongoing) 2. Conduct a single-dose pharmacokinetics study in neonates/infants aged 0 to <3 mo. Required under PREA (pending) 3. Conduct a phase 3, randomized, comparator-controlled study of dalbavancin in children aged 3 mo to 17 y with ABSSSI. Required under PREA (pending) 4. Conduct a phase 3, randomized, comparator-controlled study of dalbavancin in neonates/infants from birth to age <3 mo with ABSSSI. Required under PREA (pending) 5. Conduct U.S. surveillance studies for 5 y from the date of marketing Dalvance to determine whether resistance to dalbavancin has developed in those organisms specific to the indication in the label for ABSSSI. Required under FDAAA (pending) 6. Conduct studies to define the mechanism(s) of resistance for isolates identified as being resistant to dalbavancin during the surveillance period (5 y from the date of marketing). Required under FDAAA (pending) 9. Conduct an in vitro study evaluating interactions between dalbavancin hydrochloride and coagulation tests. Required under FDAAA (pending) Tedizolid 1. Conduct a randomized, single-blind, multicenter safety and efficacy study of intravenous to oral Sivextro (tedizolid phosphate) and intravenous to oral comparator for the treatment of acute bacterial skin and skin structure infections in pediatric patients aged 12 to <18 y. Required under PREA (pending) 2. Conduct a randomized, single-blind, multicenter safety and efficacy study of intravenous to oral Sivextro (tedizolid phosphate) and intravenous to oral comparator for the treatment of acute bacterial skin and skin structure infections in pediatric patients aged >3 mo to <12 y. Required under PREA (pending) 3. Conduct an open-label, multicenter study of 10-14 d of IV Sivextro (tedizolid phosphate) for hospital-acquired late-onset sepsis in full-term and preterm neonates and infants aged5dto<3mo.Required under PREA (pending) Continued on following page

Annals of Internal Medicine www.annals.org Downloaded From: http://annals.org/ by a Boston University Medical Center User on 06/01/2016 Appendix Table 1—Continued

Drug PMR/Commitment (Status†) 4. Conduct a phase 1 single-dose safety and pharmacokinetic study of oral and IV Sivextro (tedizolid phosphate) in patients aged2yto<12y.Required under PREA (pending) 5. Conduct a phase 1 single-dose safety and pharmacokinetic study of oral and intravenous Sivextro (tedizolid phosphate) in inpatients aged <2 y. Required under PREA (pending) 6. Conduct U.S. surveillance studies for 5 y from the date of marketing Sivextro to determine whether resistance to tedizolid has developed in those organisms specific to the indication in the label for ABSSSI. Required under FDAAA (pending) Oritavancin 1. Conduct an open-label, dose-finding, pharmacokinetics, safety, and tolerability study of Orbactiv (oritavancin diphosphate) single-dose infusion in pediatric patients aged <18 y with suspected or confirmed bacterial infections. Required under PREA (pending) 2. Conduct a multicenter, evaluator-blinded, randomized study to evaluate the safety and tolerability of single-dose IV Orbactiv (oritavancin diphosphate) versus vancomycin for the treatment of pediatric patients aged <18 y with ABSSSI. Required under PREA (pending) 3. Conduct a U.S. surveillance study over a 5-y period from the date of marketing Orbactiv (oritavancin diphosphate) to determine whether resistance to oritavancin has developed in those organisms specific to the indication in the label for ABSSSI. Required under FDAAA (pending) 4. Conduct an open-label trial evaluating the safety of a single 1200 mg IV dose of Orbactiv (oritavancin diphosphate) in patients on concomitant chronic warfarin therapy who are being treated for ABSSSI. Required under FDAAA (pending) 5. Conduct an open-label trial to assess the clinical significance of the drug–drug interaction between a single 1200-mg IV dose of Orbactiv (oritavancin diphosphate) and warfarin in healthy volunteers. Required under FDAAA (pending) 6. Conduct a single-center, open-label trial to evaluate the effects of a single 1200-mg IV dose of Orbactiv (oritavancin diphosphate) on the results of multiple coagulation tests in healthy volunteers. Required under FDAAA (pending) 7. Conduct a study to evaluate the effects of oritavancin on phospholipid- and non–phospholipid-based coagulation tests in vitro. Required under FDAAA (pending) Ceftolozane– 1. Conduct a randomized, double-blind, multicenter, comparative study to establish the safety and tolerability profile of tazobactam ceftolozane–tazobactam compared with that of meropenem in hospitalized children from birth to age <18 y with CUTI. The dose for this study will be determined upon review of the data to be submitted by December 2016 from a single-dose, multicenter, noncomparative study assessing the pharmacokinetics of ceftolozane–tazobactam in pediatric patients ages 0 to <18 y that was initiated in June 2014. Required under PREA (pending) 2. A randomized, double-blind, multicenter, comparative study to establish the safety and tolerability profile of ceftolozane–tazobactam compared with that of meropenem in hospitalized children from birth to age <18 y with CIAI. The dose for this study will be determined upon review of the data to be submitted by December 2016 from the single-dose, multicenter, noncomparative study assessing the pharmacokinetics of ceftolozane–tazobactam in pediatric patients aged 0 to <18 y that was initiated in June 2014. Required under PREA (pending) 3. Conduct a prospective study over a 5-y period after the introduction of Zerbaxa (ceftolozane–tazobactam) to the market to determine whether decreased susceptibility to Zerbaxa (ceftolozane–tazobactam) is occurring in the target population of bacteria that are in the approved Zerbaxa (ceftolozane–tazobactam) label. Required under FDAAA (pending) Ceftazidime–avibactam 1. Conduct a randomized, multicenter, active-controlled trial to evaluate the safety and tolerability of Avycaz (ceftazidime–avibactam) in children aged 3 mo to <18 y with CUTI. The dose for this study will be determined upon review of the data to be submitted by June 2015 from a single-dose, multicenter, noncomparative study assessing the pharmacokinetics of Avycaz (ceftazidime–avibactam) in pediatric patients aged 3 mo to <18 y. Required under PREA (pending) 2. Conduct a randomized, multicenter, active-controlled trial to evaluate the safety and tolerability of Avycaz (ceftazidime–avibactam) in children aged 3 mo to <18 y with CIAI. The dose for this study will be determined upon review of the data to be submitted by June 2015 from a single-dose, multicenter, noncomparative study assessing the pharmacokinetics of Avycaz (ceftazidime–avibactam) in pediatric patients aged 3 mo to <18 y. Required under PREA (pending) 3. Conduct a trial to evaluate the pharmacokinetics, safety, and tolerability of Avycaz (ceftazidime–avibactam) in children from birth to age <3 mo with late-onset sepsis. Required under PREA (pending) 4. Conduct a prospective study over a 5-y period after the introduction of Avycaz (ceftazidime–avibactam) to the market to determine whether decreased susceptibility to Avycaz (ceftazidime–avibactam) is occurring in the target population of bacteria that are in the approved Avycaz (ceftazidime–avibactam) label. Required under FDAAA (pending) 5. Conduct a trial or submit data from the phase 3 trial in CIAI to evaluate the pharmacokinetics, safety, and clinical outcomes in adult patients with baseline renal impairment (creatinine clearance ≤50 mL/min) receiving Avycaz (ceftazidime–avibactam) dosing regimens adjusted for renal function. Required under FDAAA (ongoing) ABSSSI = acute bacterial skin and skin-structure infection; CABP = community-acquired bacterial pneumonia; CIAI = complicated intra-abdominal infection; CSF = cerebrospinal fluid; CUTI = complicated urinary tract infection; FDA = U.S. Food and Drug Administration; FDAAA = FDA Amendments Act; IV = intravenous; MDR-TB = multidrug-resistant tuberculosis; MIC = minimum inhibitory concentration; MRSA = methicillin- resistant ; PREA = Pediatric Research Equity Act; PMR = postmarket requirement. * Some numbers are not listed because they were not found in the FDA database. † Pending: The study has not been initiated (i.e., no participants have been enrolled or animals dosed), but does not meet the criterion for delayed (i.e., the original projected date for initiation of patient accrual or initiation of animal dosing has not passed). Ongoing: The study is proceeding according to, or is ahead of, the original schedule. Delayed: The progression of the study is behind the original study schedule. Terminated: The applicant ended the study before completion, and has not yet submitted a final study report to the FDA. Submitted: The applicant has concluded or terminated the study and has submitted a final study report to the FDA, but FDA has not yet notified the applicant in writing that the study commitment has been fulfilled or that the commitment has been released. Fulfilled: The applicant has submitted the final study report for the commitment, and upon review of the final study report, FDA is satisfied that the applicant has met the terms of the commitment. Released: FDA has informed the applicant that it has been released from its obligation to conduct the postmarketing study because the study is either no longer feasible or would no longer provide useful information.

www.annals.org Annals of Internal Medicine Downloaded From: http://annals.org/ by a Boston University Medical Center User on 06/01/2016 Downloaded From:http://annals.org/ bya Boston University MedicalCenter Useron06/01/2016 naso nenlMedicine Internal of Annals

Appendix Table 2. Detailed Dose, Duration, and Cost of Antibiotic Drugs and Trial Comparators

New Antibiotic Comparator Cost Ratio

Drug Dose and Duration AWP Unit Unit Cost Range, $ Drug Dose and Duration AWP Unit Price Unit Cost Range, $ Price, $* Range, $*

Ceftaroline CABP: 600 mg every 166.63 600 mg CABP: 1666.30–2332.82 CABP: Ceftriaxone CABP: Ceftriaxone, 1 g CABP: 1.80– 47.05 Ceftriaxone, 1 g CABP: 9.00–329.35 CABP: 185:1 to 7:1 12 h for 5–7 d once daily for 5–7 d ABSSSI: 600 mg ABSSSI: ABSSSI: ABSSSI: Vancomycin, 1 g ABSSSI: vancomycin, Vancomycin, 1 g, plus ABSSSI: 470.10–1681.68 ABSSSI: 4:1 to 3:1 every 12 h for 1666.30–4665.64 Vancomycin + twice daily plus 7.47–20.52; aztreonam, 5–14 d aztreonam aztreonam,1gtwice aztreonam, 39.54 1g daily for 5–14 d Fidaxomicin 200 mg twice daily 198.46 200 mg 3969.20 Vancomycin† 125-mg capsule 4 times 31.30–34.80 125 mg 1252.00–1392.00 3:1 for10d daily for 10 d Bedaquiline 400 mg daily for 2 191.49 100 mg 36 000.12 Placebo (both –‡ –‡ –‡ –‡ –‡ wk, then 200 mg groups received 3 times/wk for 22 a background wk multidrug anti–TB treatment regimen) Dalbavancin One dose of 1000 1788.00 500 mg 5364.00 Vancomycin or Vancomycin, 1 g twice Vancomycin: Vancomycin, 1 g Vancomycin: 44.82–574.56 Vancomycin: 120:1 mg ,then 500 mg linezolid daily for 3–14 d, with 7.47–20.52 Linezolid, 600 mg Linezolid: 2938.72 to 9:1 8 d later optional switch to Linezolid: 183.67 Linezolid: 2:1 linezolid, 600 mg twice daily for 8 d Tedizolid 200 mg once daily Oral: 354.00 200 mg Oral: 2124 Linezolid 600 mg twice a day for 183.67 600 mg 3673.40 Oral 0.5:1 for 6 d IV: 282.00 IV: 1692 10 d IV 0.5:1 Oritavancin 1200 mg dose 1160.00 400 mg 3480.00 Vancomycin 1 g every 12 h for 7–10 d 7.47–20.52 1 g 104.58–410.40 33:1 to 9:1 administered by IV once Ceftolozane– CUTI: 1.5 g every 8 99.60 1.5 g CUTI: 2091.60 CUTI: Levofloxacin CUTI: Levofloxacin, 750 CUTI: 0.05–0.10 Levofloxacin, 750 mg CUTI: 0.35–0.70 CUTI: 5976:1 to tazobactam hfor7d mg daily for 7 d 2988:1 CIAI:1.5 g every 8 h CIAI: 1195.20–4183.20 CIAI: Meropenem CIAI: Meropenem, 1 g CIAI: 12.85–70.37 Meropenem, 1 g CIAI: 154.20–2111.10 CIAI: 8:1 to 2:1 for 4–14 d every8hfor4–10d Ceftazidime– CUTI: 2.5 g every 8 342.00 2.5 g CUTI: 7182–14 364 CUTI: CUTI: Imipenem– CUTI: 12.60–30.00 Imipenem–cilastatin, CUTI: 352.80–1680.00 CUTI: 20:1 to 9:1 avibactam h for 7–14 d Imipenem– cilastatin, 500 mg 500 mg cilastatin every6hfor7–14d (optional switch to ciprofloxacin after 4 d) CIAI: 2.5 g every 8 h CIAI: 5130–14 364 CIAI: Meropenem CIAI: Meropenem, 1 g CIAI:12.85–70.37 Meropenem, 1 g CIAI: 192.75–2955.54 CIAI: 27:1 to 5:1 for5–14d+MTZ every8hfor5–14d ABSSSI = acute bacterial skin and skin-structure infection; AWP = average wholesale price; CABP = community-acquired bacterial pneumonia; CIAI = complicated intra-abdominal infection; CUTI = complicated urinary tract infection; IV = intravenous; MTZ = metronidazole; TB = tuberculosis. † Although the fidaxomicin trials used oral vancomycin (cost shown here), some hospitals may compound generic IV into oral capsules, greatly reducing the cost. ‡ Background multidrug anti-TB regimen varied by individual. Possible drugs included ethionamide, kanamycin, ofloxacin, pyrazinamide, and terizidine (all off-patent). www.annals.org