ﺑﺴﻢ اﷲ اﻟﺮﺣﻤﻦ اﻟﺮﺣﻴﻢ Cephradine Bioequivalence and its Interaction with Khat and Food (Al-Sayadeyah) in Yemen A thesis submitted By Abdulkarim Kassem Yehia Kassem (B. Pharm., University of Khartoum) In fulfillment of the requirements of University of Khartoum for Master degree Under the supervision of Dr. Sumia Sir Elkhatim Mohamed (B. Pharm., M. Pharm., Ph.D.) Associate professor of pharmaceutics Department of Pharmaceutics Faculty of pharmacy University of Khartoum Co - supervision of Dr. Adnan Abdu Hussein Al-Adhal (B. Pharm., M. Pharm., Ph.D.) Assistant Professor of Pharmacology Department of Pharmacology Faculty of pharmacy University of Sana’a May, 2004 Dedication To my Brother, Abdu Al-Rahman Mohammad Nser Al-Shamiri Acknowledgments I would like to express my gratitude to my supervisor associate Professor Sumia Sir Elkhatim Mohamed, Head Department of Pharmaceutics, Faculty of Pharmacy, University of Khartoum for her valuable advise, continued assistance and guidance since my enrollment as postgraduate in the Graduate College, University of Khartoum, up to this stage of the work. My thanks also go to my external supervisor assistant Professor Adnan Al-Adhal, Department of Pharmacology, Sana'a University for his supervision, guidance, valuable suggestions and continued evaluation. My thanks are extended to Dr. Ahmad Al-Meklafi for his valuable advice, and to Dr. Yehya Ragaa for his support in statistical evaluation of my data. I would like to express my appreciation to my friends Rafied who prepared common Yemeni food (Al-Sayadeyah), Gamdan who prepared Khat also Yaser, Mohammed, Abdullah Taha and Qais who helped me for samples analysis. Finally many thanks to all volunteers and every body who helped me in this research. Abstract The pharmacokinetic parameters and bioequivalence of three oral brands of cephradine capsules were estimated and compared to that of reference standard product. The study was carried out in eight healthy, adult, male Yemeni volunteers after fully understood the purpose of the study and give their approval in a written consent form. Four – way crossover trials were performed using a single dose (500 mg) of cephradine on an empty stomach preceded by an overnight fast. Urine samples were collected at specified time intervals following the drug administration. Volunteers were allowed to take only water to enhance dieresis until 2 hours after medication. Standard breakfast was then served. A 7 days washout period was allowed between trials. The urine samples were kept at 4 C0 only one day till analysis. Samples were analyzed by HPLC system. The pharmacokinetic parameters (Mean ± SD) of the percentage dose excreted unchanged in urine over 12 hrs (PDE%) and the maximum peak of the urinary excretion rate (MPE, mg/min) together with the time taken to reach this peak (TTP, hrs) were used to describe the extent and rate of bioavailability respectively. The extent of cephradine bioavailability, expressed as PDE%, for brands A, B, C, and D was in the order D > A > B > C (75.3 ± 13.9, 74.2 ± 10.6, 72.8 ± 17.4 and 69.8 ± 13.6, respectively). The rate of cephradine bioavailability, expressed as MPE, for the four brands was in the order D > A > B > C (4.3 ± 0.8, 4.1 ± 1.37, 3.98 ± 0.86 and 3.7 ± 1.4, respectively). The values of TTP for the four brands (C > A = B = D) were found to be highly comparable (1.3 ± 0.56, 0.84 ± 0.25, 0.84 ± 0.25and 0.84 ± 0.25, respectively). The half lives for brand A, B, C and D are 0.71, 0.94, 0.98 and 0.84, respectively and the elimination rate constants for brand A, B, C and D were 0.98, 0.73, 0.71 and 0.83, respectively. The relative bioavailability of each of the three brands B, C and D compared to the reference brand A is in the range 80 - 120 %. Statistical analysis using student’s t-test showed that there are no statistically significant differences in all pharmacokinetic parameters between the three brands B, C and D and the reference standard product A (Pֿ> 0.05). However, TTP of brand C was > found to be significantly different compared to brand A (Pֿ 0.05). Studies on the effect of Khat and common Yemeni food (Al- Sayadeyah) on the bioavailability of reference brand A were performed in the same way as the bioequivalence studies, except that the drug was administered with khat in the first trial and with food in the second one. The results of these studies are summarized in the following table: Parameter Brand A Brand A Brand A Fasting with Khat with Al-Sayadeyah PDE (%) 74.2 ± 10.6 51.6±10 55.3±19.8 MPE, (mg/min) 4.1 ± 1.37 2.6± 0.6 1.9 ± 0.8 TTP (h) 0.84 ± 0.25 2.2 ±0.7 3.1 ± 0.9 t½ (hr) 0.71 0.5 0.72 -1 Ke (hr ) 0.98 1.4 0.96 Statistical analysis using student’s t-test showed that there are statistically significant differences in all pharmacokinetic parameters when Brand A is given in fasting condition and with either Khat or Al-Sayadeyah (P < 0.05). Khat and Al-Sayadeyah effect in the bioavailability of cephradine and decrease absorption of cephradine 50 %. The study concluded that the four brands A, B, C and D are bioequivalent and they can be used interchangeable. Bioequivalence studies were recommended to be performed for all oral dosage forms locally marketed and manufactured before issuing their certificate of registration. The study recommended the avoidance of chewing Khat and eating Al-Sayadeyah for at least three hours following cephradine and similar drugs administration. ﻣﻠﺨﺺ اﻟﺒﺤﺚ ﺗﺸﺘﻤﻞ هﺬﻩ اﻷﻃﺮوﺣﺔ ﻋﻠﻰ ﺣﺴﺎب وﻣﻘﺎرﻧﺔ اﻟﺤﺮآﻴﺔ اﻟﺪواﺋﻴﺔ واﻟﺘﻜﺎﻓﺆ اﻟﺤﻴﻮي ﻷرﺑﻌﺔ أﺻﻨﺎف ﻣﻦ اﻟﺴﻴﻔﺮادﻳﻦ ﻋﻦ ﻃﺮﻳﻖ اﻟﻔﻢ. ﺗﻤﺖ هﺬﻩ اﻟﺪراﺳﺔ ﺑﻤﺸﺎرآﺔ ﺛﻤﺎﻧﻴﺔ ﻣﻦ اﻟﻤﺘﻄﻮﻋﻴﻦ، اﻟﺒﺎﻟﻐﻴﻦ، اﻷﺻﺤﺎء، اﻟﺬآﻮر اﻟﻴﻤﻨﻴﻴﻦ. ﺷﺎرك اﻟﻤﺘﻄﻮﻋﻴﻦ ﺑﻌﺪ ﻓﻬﻤﻬﻢ اﻟﻬﺪف واﻟﻔﺎﺋﺪة اﻟﻤﺮﺟﻮة ﻣﻦ إﻗﺎﻣﺔ هﺬﻩ اﻟﺪراﺳﺔ وﺳﺠﻠﻮا ﻣﻮاﻓﻘﺘﻬﻢ آﺘﺎﺑﺔ. اﺗﺒﻌﺖ اﻟﺘﺠﺎرب اﻹآﻠﻴﻨﻴﻜﻴﺔ ﻃﺮﻳﻘﺔ اﻻﺧﺘﻴﺎر اﻟﻌﺸﻮاﺋﻲ ﻟﺠﺮﻋﺔ واﺣﺪة ﻣﻦ اﻟﻌﻘﺎر ﺗﻌﻄﻰ ﻟﻠﻤﺘﻄﻮع ﺻﺒﺎﺣﺎ ﻋﻠﻰ ﻣﻌﺪة ﻓﺎرﻏﺔ ﺑﻌﺪ ﺻﻴﺎم ﻃﻮل اﻟﻠﻴﻞ . أﺟﺮﻳﺖ هﺬﻩ اﻟﺘﺠﺎرب ﻓﻲ أرﺑﻊ ﻓﺘﺮات زﻣﻨﻴﺔ (أرﺑﻌﺔ ﺗﺠﺎرب إآﻠﻴﻨﻴﻜﻴﺔ)، ﺗﺒﻌﺪ آﻞ ﺗﺠﺮﺑﺔ ﻋﻦ اﻷﺧﺮى أﺳﺒﻮع وهﻲ اﻟﻔﺘﺮة اﻟﻜﺎﻓﻴﺔ ﻟﺘﻨﻘﻴﺔ اﻟﺠﺴﻢ ﻣﻦ ﺟﺮﻋﺔ اﻟﺴﻴﻔﺮادﻳﻦ اﻟﺴﺎﺑﻘﺔ. ﺳﻤﺢ ﻟﻠﻤﺘﻄﻮﻋﻴﻦ ﺑﻌﺪ ﺗﻌﺎﻃﻲ اﻟﻌﻘﺎر ﺑﺘﻨﺎول اﻟﻤﺎء ﻓﻘﻂ ﻟﺘﺤﻔﻴﺰ إدرار اﻟﺒﻮل ﺣﺘﻰ ﻣﺮورﺳﺎﻋﺘﻴﻦ ﻣﻦ أﺧﺬ اﻟﺠﺮﻋﺔ ﺣﻴﺚ ﻳﺤﻴﻦ ﻣﻮﻋﺪ ﺗﻨﺎول وﺟﺒﺔ اﻹﻓﻄﺎر. ﺗﻢ أﺧﺬ اﻟﺠﺮﻋﺔ ﻣﻦ اﻟﺴﻴﻔﺮادﻳﻦ وﺗﻢ أﺧﺬ ﻋﻴﻴﻨﺎت اﻟﺒﻮل ﻓﻲ اﻟﺰﻣﻦ اﻟﻤﺤﺪد وﺗﻢ ﺣﻔﻈﻬﺎ ﻓﻲ درﺟﺔ ﺣﺮارة أرﺑﻌﺔ درﺟﺔ ﻣﺌﻮﻳﺔ إﻟﻰ اﻟﻴﻮم اﻟﺜﺎﻧﻲ ﻣﻦ أﺧﺬهﺎ ﺣﻴﺚ ﺗﻢ ﺗﺤﻠﻴﻠﻬﺎ ﺑﻮاﺳﻄﺔ اﻟﺘﺤﻠﻴﻞ اﻟﻜﺮوﻣﺎﺗﻮﻏﺮاﻓﻲ ﺗﻢ ﺣﺴﺎب ﻣﺘﻮﺳﻂ اﻟﻨﺴﺒﺔ اﻟﻤﺌﻮﻳﺔ ﺑﺸﻜﻠﻬﺎ ﻏﻴﺮ اﻟﻤﺴﺘﻘﻠﺐ ﻓﻲ اﻟﺒﻮل ﺧﻼل 12 ﺳﺎﻋﺔ واﻟﺤﺪ اﻷﻋﻠﻰ ﻟﻺﻃﺮاح اﻟﺒﻮﻟﻲ ﻣﻊ اﻟﺰﻣﻦ اﻟﻼزم ﻟﻠﻮﺻﻮل إﻟﻰ هﺬا اﻟﺤﺪ. ﻗﺪ أﻇﻬﺮت اﻟﺪراﺳﺔ أن ﻣﺘﻮﺳﻂ اﻟﻨﺴﺐ اﻟﻤﺌﻮﻳﺔ ﻟﻠﺘﻮاﻓﺮ اﻟﺤﻴﻮي ﻟﻠﺴﻴﻔﺮادﻳﻦ آﺎﻧﺖ ﻋﻠﻰ اﻟﺸﻜﻞ اﻟﺘﺎﻟﻲ:D > A > B > C (and 69.8 ± 13.6 17.4 ± 72.8 ,10.6 ± 74.2 ,13.9 ± 75.3 ﻋﻠﻰ اﻟﺘﻮاﻟﻰ). آﻤﺎ أن اﻟﺤﺪ اﻷﻋﻠﻰ ﻟﻺﻃﺮاح هﻮ: D > A > B > C ) (4.3 ± 0.8, 4.1 ± 1.37, 3.98 ± 0.86 and 3.7 ± 14) آﻤﺎ أن ﻣﺘﻮﺳﻂ اﻟﺰﻣﻦ اﻟﻼزم ﻟﻠﻮﺻﻮل إﻟﻰ اﻟﺤﺪ اﻷﻋﻠﻰ ﻟﻺﻃﺮاح هﻲ: C > A = B = D 1.3 ± 0.56 >0.84 ± 0.25 = 0.84 ± 0.25 = 0.84 ± 0.25 وﻗﺪ أﻇﻬﺮ اﻟﺘﺤﻠﻴﻞ اﻹﺣﺼﺎﺋﻲ ﻟﻠﻨﺘﺎﺋﺞ أﻧﻪ ﻻ ﺗﻮﺟﺪ ﻓﻮارق ذات دﻻﻻت إﺣﺼﺎﺋﻴﺔ ﺑﻴﻦ آﻞ ﻣﻦ اﻟﻤﺴﺘﺤﻀﺮات اﻟﺜﻼﺛﺔ ﻣﻘﺎرﻧﺔ ﻣﻊ اﻟﻤﺴﺘﺤﻀﺮ اﻟﻘﻴﺎﺳﻲ ﻣﺎﻋﺪا ﻓﻲ اﻟﺰﻣﻦ اﻟﻼزم ﻟﻠﻮﺻﻮل ﻟﻠﺤﺪ اﻷﻋﻠﻰ ﻟﻺﻃﺮاح ﻟﻠﻤﺴﺘﺤﻀﺮ C اﻟﺬى أﻋﻄﻰ ﻓﺎرق إﺣﺼﺎﺋﻲ ﻣﻘﺎرﻧﺔ ﻣﻊ اﻟﻤﺴﺘﺤﻀﺮ اﻟﻘﻴﺎﺳﻲ. آﺬﻟﻚ ﺧﻠﺼﺖ اﻟﺪراﺳﺔ إﻟﻰ أهﻤﻴﺔ دراﺳﺔ اﻟﺘﻜﺎﻓﺆ اﻟﺤﻴﻮي ﺑﺎﻟﻨﺴﺒﺔ ﻟﻸدوﻳﺔ اﻟﻔﻤﻮﻳﺔ اﻟﻤﺴﺘﻮردة و اﻟﻤﺼﻨﻌﺔ ﻣﺤﻠﻴﺎ ﻗﺒﻞ إﺻﺪار ﺷﻬﺎدة ﺗﺴﺠﻴﻠﻬﺎ. آﻤﺎ ﺗﻢ دراﺳﺔ ﺗﺄﺛﻴﺮ اﻟﻘﺎت وآﺬﻟﻚ اﻟﻮﺟﺒﺔ اﻟﺸﻌﺒﻴﺔ (اﻟﺼﻴﺎدﻳﺔ) ﻋﻠﻰ اﻟﺘﻮاﺟﺪ اﻟﺤﻴﻮى ﻟﻠﺼﻨﻒ A. وﻣﻦ ﺧﻼل اﻟﺪراﺳﺔ ﻟﻠﻨﺘﺎﺋﺞ وﻣﻘﺎرﻧﺘﻬﺎ ﻣﻊ ﻧﺘﺎﺋﺞ اﻟﺼﻨﻒ A ﺑﺪون اﺧﺬ اﻟﻘﺎت أو اﻟﻮﺟﺒﺔ اﻟﺸﻌﺒﻴﺔ (اﻟﺼﻴﺎدﻳﺔ) آﺎﻧﺖ اﻟﻨﺘﺎﺋﺞ آﻤﺎ ﻳﻠﻲ: وﺟﻪ اﻟﻤﻘﺎرﻧﺔ اﻟﺼﻨﻒ A اﻟﺼﻨﻒ A ﻣﻊ اﻟﻘﺎت اﻟﺼﻨﻒ A ﻣﻊ اﻟﺼﻴﺎدﻳﺔ 1.9 ± 0.8 2.6± 0.6 4.1 ± 1.37 MPE 55.3±19.8 51.6±10 74.2 ± 10.6 PDE% 3.1 ± 09 2.2 ±0.7 0.84 ± 0.25 TTP 0.72 0.5 0.71 t½ (hr) -1 0.96 1.4 0.98 Ke (hr ) وﻗﺪ أﻇﻬﺮ اﻟﺘﺤﻠﻴﻞ اﻹﺣﺼﺎﺋﻲ ﻟﻬﺬﻩ اﻟﻨﺘﺎﺋﺞ ﺑﺄﻧﻪ ﺗﻮﺟﺪ ﻓﻮارق ذات دﻻﻻت إﺣﺼﺎﺋﻴﺔ ﻟﻠﻤﺴﺘﺤﻀﺮ A ﻣﻊ اﻟﻘﺎت وأﻳﻀﺎ ﻣﻊ اﻟﻮﺟﺒﺔ اﻟﻴﻤﻨﻴﺔ اﻟﺼﻴﺎدﻳﺔ وﻋﻠﻴﻪ ﻳﻨﺼﺢ ﺑﻌﺪم ﺗﻨﺎول اﻟﻘﺎت واﻳﻀﺎ اﻟﺼﻴﺎدﻳﺔ أﺛﻨﺎء ﺗﻨﺎول آﺒﺴﻮﻻت اﻟﺴﻴﻔﺮادﻳﻦ واﻷدوﻳﺔ اﻟﻤﺸﺎﺑﻬﺔ ﻟﻬﺎ و ذﻟﻚ ﺧﻼل ﻓﺘﺮة ﻻ ﺗﻘﻞ ﻋﻦ ﺛﻼﺛﺔ ﺳﺎﻋﺎت ﺑﻌﺪ ﺗﻨﺎول اﻟﺪواء. ﺧﻠﺼﺖ اﻟﺪراﺳﺔ اﻟﻰ أن اﻟﻤﺴﺘﺤﻀﺮات اﻷرﺑﻌﺔ (A, B, C and D) ﻣﺘﻜﺎﻓﺌﺔ ﺣﻴﻮﻳﺎ.وأن اﻟﻘﺎت وآﺬﻟﻚ اﻟﻮﺟﺒﺔ اﻟﺸﻌﺒﻴﺔ (اﻟﺼﻴﺎدﻳﺔ) ﻳﻌﻤﻼ ﻋﻠﻰ ﻋﺪم اﻣﺘﺼﺎص %50 ﻣﻦ اﻟﺴﻴﻔﺮادﻳﻦ. Table of Contents Page i Acknowledgments Abstract (English) ii Abstract (Arabic) v Table of contents vii List of tables xi List of figures xiii Appendices xvii Abbreviations xviii Chapter 1: Introduction 1.1. Introduction and literature review 1 1.2. History of β-lactam 2 1.2.1. β - lactamase inhibitors 3 1.3. Cephalosporins History and Sources 4 1.4 Chemistry of Cephalosporins 5 1.4.1. Chemical Degradation 6 1.5. Structure activity relationship (SAR) 8 1.6. Mechanism of action of cephalosporins 9 1.6.1. Inhibition of cell wall synthesis 9 1.7. Mechanism of Bacterial resistance 10 1.8. Cephradine 11 1.8.1. Chemistry 11 1.8.2. Physical properties 12 1.8.3. Pharmacological properties 12 1.8.4. Antimicrobical activities 13 1.8.5. Cephradine drugs interaction 13 1.9. Pharmacokinetics of Drugs 14 1.9.1. Absorption 14 1.9.1.1 Factors affecting absorption 14 1.9.1.2. The gastrointestinal tract and drug absorption 26 1.9.1.3.