{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,18]],"date-time":"2026-03-18T06:13:13Z","timestamp":1773814393426,"version":"3.50.1"},"reference-count":37,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2025,3,1]],"date-time":"2025-03-01T00:00:00Z","timestamp":1740787200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FAES-FARMA S.A.","award":["ROBX-0121\/BE"],"award-info":[{"award-number":["ROBX-0121\/BE"]}]},{"name":"FAES-FARMA S.A.","award":["ZL-2022\/00685"],"award-info":[{"award-number":["ZL-2022\/00685"]}]},{"name":"FAES-FARMA S.A.","award":["ZL-2023\/00459"],"award-info":[{"award-number":["ZL-2023\/00459"]}]},{"name":"Basque Country Government (Economic Development, Sustainability and Environment Department)","award":["ROBX-0121\/BE"],"award-info":[{"award-number":["ROBX-0121\/BE"]}]},{"name":"Basque Country Government (Economic Development, Sustainability and Environment Department)","award":["ZL-2022\/00685"],"award-info":[{"award-number":["ZL-2022\/00685"]}]},{"name":"Basque Country Government (Economic Development, Sustainability and Environment Department)","award":["ZL-2023\/00459"],"award-info":[{"award-number":["ZL-2023\/00459"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pharmaceuticals"],"abstract":"<jats:p>Objective: This study aimed to assess the bioequivalence of two oral methocarbamol formulations, as follows: the test (T) methocarbamol 1500 mg tablets and the reference (R) Robaxin\u00ae 500 mg tablets (3 tablets, total dose: 1500 mg) under fasting conditions, and compare their pharmacokinetic performance. Methods: This was a single-center, phase I, randomized, open-label (blinded for analytical determination), two-sequence, two-period, crossover, bioequivalence study. A total of 32 healthy volunteers were randomly assigned to receive the T-R or R-T administration sequence. Each volunteer received a single dose of each methocarbamol formulation (T or R) separated by a washout period of 7 days. To evaluate the pharmacokinetic profile, blood samples were collected at nineteen time points after dosing. Results: The arithmetic mean Cmax was 31.72 \u00b5g\/mL for R and 32.39 \u00b5g\/mL for T, and the arithmetic mean AUC0\u2212t was 90.25 h \u00d7 \u00b5g\/mL and 89.72 h \u00d7 \u00b5g\/mL, respectively. All adverse events reported were mild for both formulations. The 90% confidence intervals for the corresponding logarithmically transformed geometric mean ratios of Cmax and AUC0\u2212t fell within the acceptance interval of 80.00\u2013125.00%, as their values were 91.67\u2013112.47% for ln(Cmax) and 92.34\u2013103.47% for ln(AUC0\u2212t). Conclusion: Therefore, one tablet of methocarbamol 1500 mg was found to be bioequivalent to the Robaxin\u00ae 500 mg tablets (3 tablets), with comparable tolerability and safety profiles.<\/jats:p>","DOI":"10.3390\/ph18030354","type":"journal-article","created":{"date-parts":[[2025,3,3]],"date-time":"2025-03-03T07:37:17Z","timestamp":1740987437000},"page":"354","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Bioequivalence Study of Two Oral Methocarbamol Formulations in Healthy Subjects Under Fasting Conditions: A Randomized, Open-Label, Crossover Clinical Trial"],"prefix":"10.3390","volume":"18","author":[{"given":"Ana","family":"Ascaso-del-Rio","sequence":"first","affiliation":[{"name":"Clinical Pharmacology Department, Hospital Cl\u00ednico San Carlos, C\/Prof Mart\u00edn Lagos s\/n, 28040 Madrid, Spain"},{"name":"Instituto de Investigaci\u00f3n Sanitaria del Hospital Cl\u00ednico San Carlos, C\/Prof Mart\u00edn Lagos s\/n, 28040 Madrid, Spain"},{"name":"Pharmacology and Toxicology Department, School of Medicine, Universidad Complutense de Madrid (UCM), 28040 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-4694-2923","authenticated-orcid":false,"given":"Paola","family":"Camargo-Mamani","sequence":"additional","affiliation":[{"name":"Clinical Research Department, Faes Farma, Av. Autonom\u00eda 10, 48940 Leioa, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Inmaculada","family":"Gilaberte","sequence":"additional","affiliation":[{"name":"Clinical Research Department, Faes Farma, Av. Autonom\u00eda 10, 48940 Leioa, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"M\u00f3nica","family":"D\u00edez-Hochleitner","sequence":"additional","affiliation":[{"name":"Clinical Research Department, Faes Farma, Av. Autonom\u00eda 10, 48940 Leioa, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Leonor","family":"Laredo-Velasco","sequence":"additional","affiliation":[{"name":"Clinical Pharmacology Department, Hospital Cl\u00ednico San Carlos, C\/Prof Mart\u00edn Lagos s\/n, 28040 Madrid, Spain"},{"name":"Instituto de Investigaci\u00f3n Sanitaria del Hospital Cl\u00ednico San Carlos, C\/Prof Mart\u00edn Lagos s\/n, 28040 Madrid, Spain"},{"name":"Pharmacology and Toxicology Department, School of Medicine, Universidad Complutense de Madrid (UCM), 28040 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Teresa","family":"Iglesias-Hernang\u00f3mez","sequence":"additional","affiliation":[{"name":"Clinical Pharmacology Department, Hospital Cl\u00ednico San Carlos, C\/Prof Mart\u00edn Lagos s\/n, 28040 Madrid, Spain"},{"name":"Instituto de Investigaci\u00f3n Sanitaria del Hospital Cl\u00ednico San Carlos, C\/Prof Mart\u00edn Lagos s\/n, 28040 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mar\u00eda Rosario","family":"Salas-Butr\u00f3n","sequence":"additional","affiliation":[{"name":"Clinical Pharmacology Department, Hospital Cl\u00ednico San Carlos, C\/Prof Mart\u00edn Lagos s\/n, 28040 Madrid, Spain"},{"name":"Instituto de Investigaci\u00f3n Sanitaria del Hospital Cl\u00ednico San Carlos, C\/Prof Mart\u00edn Lagos s\/n, 28040 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Laura","family":"Gal\u00e1n Caballero","sequence":"additional","affiliation":[{"name":"Clinical Pharmacology Department, Hospital Cl\u00ednico San Carlos, C\/Prof Mart\u00edn Lagos s\/n, 28040 Madrid, Spain"},{"name":"Instituto de Investigaci\u00f3n Sanitaria del Hospital Cl\u00ednico San Carlos, C\/Prof Mart\u00edn Lagos s\/n, 28040 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3959-8196","authenticated-orcid":false,"given":"Iv\u00e1n Alejandro","family":"D\u00edaz-Rengifo","sequence":"additional","affiliation":[{"name":"Instituto de Investigaci\u00f3n Sanitaria del Hospital Cl\u00ednico San Carlos, C\/Prof Mart\u00edn Lagos s\/n, 28040 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Carla","family":"P\u00e9rez-Ingidua","sequence":"additional","affiliation":[{"name":"Clinical Pharmacology Department, Hospital Cl\u00ednico San Carlos, C\/Prof Mart\u00edn Lagos s\/n, 28040 Madrid, Spain"},{"name":"Instituto de Investigaci\u00f3n Sanitaria del Hospital Cl\u00ednico San Carlos, C\/Prof Mart\u00edn Lagos s\/n, 28040 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4828-6004","authenticated-orcid":false,"given":"Emilio","family":"Vargas-Castrill\u00f3n","sequence":"additional","affiliation":[{"name":"Clinical Pharmacology Department, Hospital Cl\u00ednico San Carlos, C\/Prof Mart\u00edn Lagos s\/n, 28040 Madrid, Spain"},{"name":"Instituto de Investigaci\u00f3n Sanitaria del Hospital Cl\u00ednico San Carlos, C\/Prof Mart\u00edn Lagos s\/n, 28040 Madrid, Spain"},{"name":"Pharmacology and Toxicology Department, School of Medicine, Universidad Complutense de Madrid (UCM), 28040 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5646-5275","authenticated-orcid":false,"given":"Antonio","family":"Portol\u00e9s-P\u00e9rez","sequence":"additional","affiliation":[{"name":"Clinical Pharmacology Department, Hospital Cl\u00ednico San Carlos, C\/Prof Mart\u00edn Lagos s\/n, 28040 Madrid, Spain"},{"name":"Instituto de Investigaci\u00f3n Sanitaria del Hospital Cl\u00ednico San Carlos, C\/Prof Mart\u00edn Lagos s\/n, 28040 Madrid, Spain"},{"name":"Pharmacology and Toxicology Department, School of Medicine, Universidad Complutense de Madrid (UCM), 28040 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,3,1]]},"reference":[{"key":"ref_1","unstructured":"Sibrack, J., Patel, P., and Hammer, R. 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