Publications

Algorta, Jaime, Laura Andrade, Marta Medina, Valentin Kirkov, Sacha Arsova, Fumin Li, and Jingduan Chi. “Pharmacokinetic Bioequivalence of Two Inhaled Tiotropium Bromide Formulations in Healthy Volunteers.” Clinical Drug Investigation 36, no. 9 (September 2016): 753–62. doi:10.1007/s40261-016-0441-8. [FULLTEXT]

Baldamus, Conrad, Stefan Krivoshiev, Michael Wolf-Pflugmann, Marianne Siebert-Weigel, Rossen Koytchev, and Angelika Bronn. “Long-Term Safety and Tolerability of Epoetin Zeta, Administered Intravenously, for Maintenance Treatment of Renal Anemia.” Advances in Therapy 25, no. 11 (November 2008): 1215–28. doi:10.1007/s12325-008-0111-1.

Böhm, R., R. Ellrich, and R. Koytchev. “Quantitation of R- and S-Propafenone and of the Main Metabolite in Plasma.” Die Pharmazie 50, no. 8 (August 1995): 542–45.

Erkent, Ulkem, and Rossen Koytchev. “The Use of Truncated Area under the Curves in the Bioequivalence Evaluation of Long Half-Life Drugs. Studies with Donepezil and Memantine.” Arzneimittel-Forschung 58, no. 5 (2008): 255–58. doi:10.1055/s-0031-1296502.

Fuglsang, Anders, Helmut Schütz, and Detlew Labes. “Reference Datasets for Bioequivalence Trials in a Two-Group Parallel Design.” The AAPS Journal 17, no. 2 (March 2015): 400–404. doi:10.1208/s12248-014-9704-6.

Gatchev, Emil, Andrey Petrov, Emil Kolev, Russka Hristova, Irena Demircheva, Rossen Koytchev, Wolfram Richter, Friedrich Tegel, and Ursula Thyroff-Friesinger. “Pharmacodynamic Equivalence Study of Two Preparations of Eye Drops Containing Dorzolamide and Timolol in Healthy Volunteers.” Arzneimittel-Forschung 61, no. 5 (2011): 282–86. doi:10.1055/s-0031-1296200.

Gatchev, Emil, Ursula Thyroff-Friesinger, Nina Bakracheva, Valentin Kirkov, Rossen Koytchev, and Mike John van der Meer. “Analysis of Pooled Plasma Samples as a Predictor for Proving Bioequivalence of Drugs with a Long Elimination Half-Life. The Example of Phenprocoumon.” Arzneimittel-Forschung 54, no. 10 (2004): 685–89. doi:10.1055/s-0031-1297022.

Gräser, T., R. Koytchev, A. Müller, and M. Oettel. “Comparison of the Efficacy and Endometrial Safety of Two Estradiol Valerate/dienogest Combinations and Kliogest for Continuous Combined Hormone Replacement Therapy in Postmenopausal Women.” Climacteric: The Journal of the International Menopause Society 3, no. 2 (June 2000): 109–18.

Hayashi, Mikako, Kenji Okamura, Hongxia Wu, Yutaka Takahashi, Evgeni V. Koytchev, Satoshi Imazato, and Shigeyuki Ebisu. “The Root Canal Bonding of Chemical-Cured Total-Etch Resin Cements.” Journal of Endodontics 34, no. 5 (May 2008): 583–86. doi:10.1016/j.joen.2008.02.003.

Kirkov, Valentin, Velislava Dimitrova, Marianne Siebert-Weigel, Michael Wolf-Pflugmann, Rossen Koytchev, Wolfram Richter, Angelika Bronn, Sacha Arsova, and Arno Kromminga. “Evaluation of the Pharmacokinetics of Two Recombinant Human Erythropoietin Preparations: Epoetin Zeta and Epoetin Alfa. 1st Communication: A Monocentric, Open, Randomized, Single Dose, Two-Period Crossover Trial in Healthy Volunteers.” Arzneimittel-Forschung 58, no. 5 (2008): 215–19. doi:10.1055/s-0031-1296497.

———. “Evaluation of the Pharmacokinetics of Two Recombinant Human Erythropoietin Preparations: Epoetin Zeta and Epoetin Alfa. 2nd Communication: A Monocentric, Double-Blind, Randomized, Single Dose, Three-Period Crossover Trial in Healthy Volunteers.” Arzneimittel-Forschung 58, no. 5 (2008): 220–24. doi:10.1055/s-0031-1296498.

Koytchev, R., R. G. Alken, and S. Dundarov. “Balm Mint Extract (Lo-701) for Topical Treatment of Recurring Herpes Labialis.” Phytomedicine: International Journal of Phytotherapy and Phytopharmacology 6, no. 4 (October 1999): 225–30. doi:10.1016/S0944-7113(99)80013-0.

Koytchev, R., R. G. Alken, and E. Gromnica-Ihle. “Serum Concentration of Piroxicam and Inhibition of Platelet Aggregation in Patients with Rheumatoid Arthritis and M. Bechterew.” Agents and Actions 43, no. 1–2 (November 1994): 48–52.

Koytchev, R., R. G. Alken, V. Kirkov, G. Neshev, M. Vagaday, and U. Kunter. “[Absolute bioavailability of chlorpromazine, promazine and promethazine].” Arzneimittel-Forschung 44, no. 2 (February 1994): 121–25.

Koytchev, R., R. G. Alken, and O. Mayer. “Effect of Diprafenone on the Pharmacokinetics of Digoxin.” European Journal of Clinical Pharmacology 50, no. 1–2 (1996): 97–100.

Koytchev, R., R. G. Alken, O. Mayer, R. Böhm, A. Ellrich, and R. G. Waldner-Kölblin. “[The bioequivalence of two oral propafenone preparations].” Arzneimittel-Forschung 45, no. 5 (May 1995): 542–45.

Koytchev, R., R. G. Alken, O. Mayer, I. Smith, and M. Greenwood. “Influence of Food on the Bioavailability and Some Pharmacokinetic Parameters of Diprafenone–a Novel Antiarrhythmic Agent.” European Journal of Clinical Pharmacology 50, no. 4 (1996): 315–19.

Koytchev, R., R. G. Alken, G. McKay, and T. Katzarov. “Absolute Bioavailability of Oral Immediate and Slow Release Fluphenazine in Healthy Volunteers.” European Journal of Clinical Pharmacology 51, no. 2 (1996): 183–87.

Koytchev, R., R. G. Alken, M. Vagaday, U. Kunter, and V. Kirkov. “Differences in the Bioavailability of Dihydrotachysterol Preparations.” European Journal of Clinical Pharmacology 47, no. 1 (1994): 81–84.

Koytchev, R., R. G. Alken, V. Vlahov, V. Kirkov, R. Kaneva, U. Thyroff-Friesinger, and E. Rehak. “Influence of the Cytochrome P4502D6*4 Allele on the Pharmacokinetics of Controlled-Release Metoprolol.” European Journal of Clinical Pharmacology 54, no. 6 (August 1998): 469–74.

Koytchev, R., V. Vlahov, N. Bacratcheva, B. Giesel, B. Gawronska-Szklarz, J. Wojcicki, A. Mrozikiewiczs, M. van der Meer, and R. G. Alken. “Evaluation of the Efficacy of a Combined Formulation (Grippostad-C) in the Therapy of Symptoms of Common Cold: A Randomized, Double-Blind, Multicenter Trial.” International Journal of Clinical Pharmacology and Therapeutics 41, no. 3 (March 2003): 114–25.

Koytchev, Rossen, Aydin Erenmemisoglu, Mike John van der Meer, and Serdar Alpan. “Clinical Relevance of Bioequivalence Acceptance Criteria. The Example of Terbinafine.” Arzneimittel-Forschung 53, no. 4 (2003): 289–93. doi:10.1055/s-0031-1297110.

Koytchev, Rossen, and Reinhard Lauschner. “Bioequivalence Study of Levothyroxine Tablets Compared to Reference Tablets and an Oral Solution.” Arzneimittel-Forschung 54, no. 10 (2004): 680–84. doi:10.1055/s-0031-1297021.

Koytchev, Rossen, Yildiz Ozalp, Aydin Erenmemisoglu, Ulrich Kunter, and Recep Serdar Alpan. “Effect of the Formulation on the Bioequivalence of Sultamicillin: Tablets and Suspension.” Arzneimittel-Forschung 54, no. 9A (September 2004): 634–39. doi:10.1055/s-0031-1297062.

Koytchev, Rossen, Yildiz Ozalp, Aydin Erenmemisoglu, Nadejda Tyutyulkova, Emil Gatchev, and Recep Serdar Alpan. “Studies on the Bioequivalence of Second Generation Cephalosporins: Cefaclor Capsules and Suspension.” Arzneimittel-Forschung 54, no. 9A (September 2004): 583–87. doi:10.1055/s-0031-1297053.

Koytchev, Rossen, Yildiz Ozalp, Aydin Erenmemisoglu, Mike John van der Meer, and Recep Serdar Alpan. “Assessment of the Bioequivalence of Different Formulations Containing Azithromycin (Tablets and Suspension).” Arzneimittel-Forschung 54, no. 9A (September 2004): 578–82. doi:10.1055/s-0031-1297052.

———. “Bioequivalence Study of Atorvastatin Tablets.” Arzneimittel-Forschung 54, no. 9A (September 2004): 573–77. doi:10.1055/s-0031-1297051.

———. “Bioequivalence Study of Rofecoxib Tablets.” Arzneimittel-Forschung 54, no. 9A (September 2004): 624–28. doi:10.1055/s-0031-1297060.

———. “Clarithromycin Suspension: Bioequivalence Studies on Two Different Strengths.” Arzneimittel-Forschung 54, no. 9A (September 2004): 594–99. doi:10.1055/s-0031-1297055.

———. “Combination of Losartan and Hydrochlorothiazide: In Vivo Bioequivalence.” Arzneimittel-Forschung 54, no. 9A (September 2004): 611–17. doi:10.1055/s-0031-1297058.

———. “Effect of the Combination of Lisinopril and Hydrochlorothiazide on the Bioequivalence of Tablet Formulations.” Arzneimittel-Forschung 54, no. 9A (September 2004): 605–10. doi:10.1055/s-0031-1297057.

———. “Serotonin Reuptake Inhibitors: Bioequivalence of Sertraline Capsules.” Arzneimittel-Forschung 54, no. 9A (September 2004): 629–33. doi:10.1055/s-0031-1297061.

———. “Studies on the Bioequivalence of Different Strengths of Tablets Containing Clarithromycin.” Arzneimittel-Forschung 54, no. 9A (September 2004): 588–93. doi:10.1055/s-0031-1297054.

Koytchev, Rossen, Wolfram Richter, Ulkem Erkent, Valentin Kirkov, Velislava Dimitrova, Andreas Nern, and Ulrich Kunter. “Influence of Acarbose on Blood Glucose and Breath Hydrogen after Carbohydrate Load with Sucrose or Starch.” Arzneimittel-Forschung 59, no. 11 (2009): 557–63. doi:10.1055/s-0031-1296444.

Krivoshiev, Stefan, Vasil V. Todorov, Jacek Manitius, Stanislaw Czekalski, Paul Scigalla, Rossen Koytchev, and Epoetin Zeta Study Group. “Comparison of the Therapeutic Effects of Epoetin Zeta and Epoetin Alpha in the Correction of Renal Anaemia.” Current Medical Research and Opinion 24, no. 5 (May 2008): 1407–15. doi:10.1185/030079908X297402.

Krivoshiev, Stefan, Volker Wizemann, Stanisław Czekalski, Adalbert Schiller, Steva Pljesa, Michael Wolf-Pflugmann, Marianne Siebert-Weigel, Rossen Koytchev, Angelika Bronn, and Epoetin Zeta Study Group. “Therapeutic Equivalence of Epoetin Zeta and Alfa, Administered Subcutaneously, for Maintenance Treatment of Renal Anemia.” Advances in Therapy 27, no. 2 (February 2010): 105–17. doi:10.1007/s12325-010-0012-y.

Kumchev, E., R. Koytchev, D. Dimitrakov, P. Stavrev, G. Tsochev, and M. Siebert-Weigel. “Effect of Epoetin Zeta for Correction of Renal Anemia in Hemodialysis Patients with Thalassemia Minor.” Advances in Therapy 25, no. 12 (December 2008): 1375–78. doi:10.1007/s12325-008-0119-6.

Richter, Wolfram, Aydin Erenmemisoglu, Mike John Van der Meer, Nizam Emritte, Emine Tuncay, and Rossen Koytchev. “Bioequivalence Study of Two Different Clopidogrel Bisulfate Film-Coated Tablets.” Arzneimittel-Forschung 59, no. 6 (2009): 297–302. doi:10.1055/s-0031-1296400.

Schneider, Frank, Moritz Hillgenberg, Rossen Koytchev, and Rudolf-Giesbert Alken. “Enhanced Plasma Concentration by Selective Deuteration of Rofecoxib in Rats.” Arzneimittel-Forschung 56, no. 4 (2006): 295–300. doi:10.1055/s-0031-1296724.

Schneider, Frank, Emine Mattern-Dogru, Moritz Hillgenberg, and Rudolf-Giesbert Alken. “Changed Phosphodiesterase Selectivity and Enhanced in Vitro Efficacy by Selective Deuteration of Sildenafil.” Arzneimittel-Forschung 57, no. 6 (2007): 293–98. doi:10.1055/s-0031-1296622.

Stamenova, P., R. Koytchev, K. Kuhn, C. Hansen, F. Horvath, S. Ramm, and D. Pongratz. “A Randomized, Double-Blind, Placebo-Controlled Study of the Efficacy and Safety of Tolperisone in Spasticity Following Cerebral Stroke.” European Journal of Neurology 12, no. 6 (June 2005): 453–61. doi:10.1111/j.1468-1331.2005.01006.x.

Tzekova, Valentina, Georgi Mihaylov, Ivo Elezovic, Rossen Koytchev, and Epoetin Zeta Oncology Study Group. “Therapeutic Effects of Epoetin Zeta in the Treatment of Chemotherapy-Induced Anaemia.” Current Medical Research and Opinion 25, no. 7 (July 2009): 1689–97. doi:10.1185/03007990903050876.

Vlahov, V., U. Thyroff-Friesinger, R. Koytchev, N. Bakracheva, and E. Gatchev. “Bioequivalence Studies with Metformin: Comparability of Reference Tablets from Different Origins.” International Journal of Clinical Pharmacology and Therapeutics 43, no. 9 (September 2005): 457–62.

Więcek, Andrzej, Islah Ahmed, Paul Scigalla, and Rossen Koytchev. “Switching Epoetin Alfa and Epoetin Zeta in Patients with Renal Anemia on Dialysis: Posthoc Analysis.” Advances in Therapy 27, no. 12 (December 2010): 941–52. doi:10.1007/s12325-010-0080-z.

Wizemann, Volker, Boleslaw Rutkowski, Conrad Baldamus, Paul Scigalla, Rossen Koytchev, and Epoetin Zeta Study Group. “Comparison of the Therapeutic Effects of Epoetin Zeta to Epoetin Alfa in the Maintenance Phase of Renal Anaemia Treatment.” Current Medical Research and Opinion 24, no. 3 (March 2008): 625–37. doi:10.1185/030079908X273264.

Wong, Hong, Yildiz Ozalp, Audrey Lainesse, and Recep Serdar Alpan. “In Vivo Bioequivalence of Oral Antidiabetic Agents: Pioglitazone Tablets.” Arzneimittel-Forschung 54, no. 9A (September 2004): 618–24. doi:10.1055/s-0031-1297059.

Wu, Hongxia, Mikako Hayashi, Kenji Okamura, Evgeni V. Koytchev, Satoshi Imazato, Saori Tanaka, Yuko Tanaka, Hidehiko Sano, and Shigeyuki Ebisu. “Effects of Light Penetration and Smear Layer Removal on Adhesion of Post-Cores to Root Canal Dentin by Self-Etching Adhesives.” Dental Materials: Official Publication of the Academy of Dental Materials 25, no. 12 (December 2009): 1484–92. doi:10.1016/j.dental.2009.06.019.

Zimmermann, H., R. Koytchev, O. Mayer, A. Börner, U. Mellinger, and H. Breitbarth. “Pharmacokinetics of Orally Administered Estradiol Valerate. Results of a Single-Dose Cross-over Bioequivalence Study in Postmenopausal Women.” Arzneimittel-Forschung 48, no. 9 (September 1998): 941–47.