Letters to editor

Dysmorphic child born after maternal therapy

Access this article online showed absent left kidney. Family history revealed that the Quick Response Code: other siblings were normal, without any dysmorphic facies Website: www.ijp-online.com or systemic abnormality.With a history of maternal intake of DOI: 10.4103/0253-7613.77385 diclofenac during early pregnancy and normal family history, it can be postulated that a high dose diclofenac could have been responsible for the multiple anomalies seen in this patient. This can be considered as a possible adverse drug reaction as per causality assessment, on Naranjo’s scale. Sir, Diclofenac is a non-steroidal, anti-inflammatory drug, A five-month-old baby was brought with complaints of widely prescribed in India to women of child bearing age abnormal facial features. A detailed birth and past history for the treatment of various conditions, including arthritis, revealed that the baby was the third child, born of a non- musculo-skeletal pain, dysmenorrhea, and menorrhagia. The consanguineous marriage. The mother was prescribed tablet primary mechanism responsible for its action is inhibition of diclofenac sodium (100 mg thrice daily) by a general practitioner synthesis via the cyclo-oxygenase .[1] It is for joint pain during the first trimester of pregnancy. The joint placed under ‘category C’ in the ‘United States Food and Drug pain disappeared after four days. However, she continued Administration’ classification of the pregnancy categories for taking tablet diclofenac on her own. There was no significant pharmaceuticals.[2] Even though conclusive evidence about antenatal history suggestive of systemic disease. She delivered the teratogenecity of diclofenac in human embryos is lacking, a full-term baby boy, with a birth weight of 2.25 kg, and was animal studies have shown that administration of the drug at discharged on breast feeds on the second postnatal day. a high concentration, in early gestation, inhibits implantation After three months an echocardiography was done in view of and embryonic development.[1] It crosses the human placenta recurrent lower respiratory tract . It showed a 4.5 readily during the first trimester and should be considered as mm non-restrictive patent ductus arteriosus (left to right), 4 potentially teratogenic.[3] Ventricular septal defect and aplasia mm atrial septal defect (left to right), and severe pulmonary cutis congenita have been reported in babies born to mothers artery hypertension. On examination, the head circumference on diclofenac therapy.[4,5] The drug is known to accumulate in was 41 cm., weight was 3.1 kg, and length was 58 cm (below the fifth percentile for age and gender), suggestive of failure the fetal tissue with time. It is usually prescribed in multiple to thrive. Dysmorphic facies were present in the form of low doses, thereby resulting in a high probability of fetal tissue [1] set and deformed external ears. Oral cavity examination concentration reaching the teratogenic level. The exact revealed a high arched palate. He also had hypertelorism and mechanism of diclofenac-induced teratogenecity is uncertain. It wide spaced nipples [Figure 1]. Serologic tests for toxoplasma, may result from free oxygen radical damage to the developing rubella, cytomegalovirus, and herpes simplex were negative. embryo. Also, it has been postulated that by inhibiting the The complete blood count, ultrasound of the skull, and synthesis of vasodilatory , diclofenac can cause chromosomal analysis was normal. Ultrasound of the abdomen transient vasoconstriction and decreased blood supply, resulting in malformation and cellular death.

Figure 1: Clinical Photograph of the child showing dysmorphic facies Acknowledgement in the form of low set and deformed external ears. Also seen is the presence of hypertelorism and wide spaced nipples We would like to thank Dr. Sandhya Kamath, Dean of our institution, for permitting us to publish this manuscript.

Syed Ahmed Zaki, Angadi Rajasab Nilofer1, Preeti Shanbag Department of Pediatrics, Lokmanya Tilak Municipal Medical College and General Hospital, Mumbai, 1Department of Obstetrics and Gynaecology, Jaya Jagadguru Murugharajendra Medical College, Davangere, Karnataka, India

Correspondence to: Dr. Syed Ahmed Zaki, Room no 509, New RMO quarters, Shastri Galli, Sion, Mumbai - 22, India E-mail: [email protected]

220 Indian Journal of Pharmacology | April 2011 | Vol 43 | Issue 2 Letters to editor

References United States of America: McGraw-Hill Companies; 2010. p. 315. 3. Siu SS, Yeung JH, Lau TK. A study on placental transfer of diclofenac in first 1. Chan LY, Chiu PY, Siu SSN, Lau TK: A study of diclofenac-induced teratogenecity trimester of human pregnancy. Hum Reprod 2000;15:2423-5. during organogenesis using a whole rat embryo culture model. Hum Reprod 4. Pajaziti L, Rexhepi S, Shatri-Muça Y, Ferizi M. The role of diclofenack on inducing 2001;16:2390-3. of aplasia cutis congenita: A case report. Cases J 2009;2:150. 2. Teratology and medications that affect the fetus. In: Cunningham FG, Leveno KJ, 5. Ericson A, Källén BA. Nonsteroidal anti-inflammatory drugs in early pregnancy. Bloom SL, Hauth JC, Rouse DJ, Spong CY, editors. Williams Obstetrics. 23rd ed. Reprod Toxicol 2001;15:371-5.

Regulatory filing strategy for generic mesalazine modified release formulations

significant differences, if any, between the mesalazine release Access this article online profiles of the test and reference products, at the site of Quick Response Code: Website: www.ijp-online.com action. Pharmacokinetic profiles, specifically, can be analyzed

DOI: 10.4103/0253-7613.77386 over defined time intervals using partial AUC or other profile comparison tools (including, but not limited to, mean residence

time and a steady state Cmax). Using these tools, the US FDA can analyze systemic mesalazine concentrations, over specified time intervals, to determine whether mesalazine from the test and reference products is absorbed at the same rate and to the same extent at the colon and . In addition to this, if the Sir, products have equivalent in vitro dissolution characteristics, Mesalazine, also known as mesalamine or 5-aminosalicylic the agency can further conclude that drug availability at those acid (5-ASA), is an anti-inflammatory drug used to treat sites of action is the same.[4,5] ulcerative and Crohn’s disease. The efficacy of mesalazine On account of the intended topical and targeted nature of formulations in seem to depend on the pH at mesalazine, it was argued that new mesalazine products should which they release the drug. If the drug is released at pH ≥ 7, meet a more stringent set of clinical requirements than merely it is effective in cases involving the terminal ileum and colon. relying on systemic bioequivalence data. Hence, earlier it was If the affected site is ileal, release at pH ≥ 6 might be more suggested that a comparative should be conducted effective. The oral mesalazine formulations use various coatings to determine the therapeutic equivalence, in addition to in vitro or protective characteristics that release the drug under specific dissolution and in vivo bioequivalence data.[1,2] However, in a conditions, targeting the distal . These recent development, the US FDA has continued to recommend preparations exhibit different and individual in vitro release in vitro dissolution testing, but now recommends comparative characteristics, resulting in different availabilities of the drug at pharmacokinetic studies rather than clinical endpoint studies different sites in the gastrointestinal tract, and hence, different to show the bioequivalence of mesalazine products. The pharmacokinetic parameters. Due to the different profiles of agency has further stated that comparative clinical endpoint these modified release products, it is currently recommended studies will be less sensitive, accurate, and reproducible than that the available mesalazine formulations should not be used pharmacokinetic studies.[5] interchangeably, and should be prescribed by their proprietary The development of generic mesalazine preparations with name.[1-3] non-identical delivery systems can be seen as a special case, as The regulatory approval of generic mesalazine formulations substitution will inevitably not create an identical effect, even has been a knotty issue and the relevance of the comparative though the principal active agent is the same. On account of pharmacokinetic and clinical endpoint studies has been debated the intended topical and targeted nature of mesalazine, it was for long. In view of the above, current recommendations for the earlier suggested that the new mesalazine products should regulatory filing of the generic oral modified release mesalazine meet a more stringent set of clinical requirements than merely products are discussed herewith. relying on systemic bioequivalence data. However, in a recent To ensure that any new mesalazine product is development, the US FDA has recommended in vitro dissolution pharmaceutically equivalent to an already marketed formulation, testing in addition to comparative pharmacokinetic studies, based on the available evidence, it would be necessary to rather than clinical endpoint studies, to show the bioequivalence establish comparable in vitro dissolution. The US FDA (Food of these products. The US FDA believes that pharmacokinetic and Drug Administration) states that in vitro dissolution testing studies will better detect the significant differences, if any, in should be conducted over a range of pHs, reflective of the the drug release patterns of the test and reference formulations expected conditions in the GI (gastrointestinal) tract.[1] of mesalazine at the sites of drug action. The US FDA has recently recommended that if the pharmacokinetic data are analyzed using other metrics in lieu Acknowledgement of or in addition to AUC and Cmax, then it is possible to detect I gratefully acknowledge the help of anonymous reviewers

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