Persiani S, Sala F, Manzotti C, Colovic M, Zangarini M, Donazzolo Y, Barbetta B, Vitalini C, Giacovelli G, Benvenuti C, Rovati L C
Rottapharm Biotech S.r.l., Monza, Italy.
Eurofins|OPTIMED Clinical Research, Gieres, France.
Drug Res (Stuttg). 2016 Mar;66(3):136-40. doi: 10.1055/s-0035-1555784. Epub 2015 Jun 30.
Post-menopausal women under treatment with levothyroxine for their medical conditions may take concomitantly dietary supplements containing soy isoflavones in combination to treat their post-menopausal symptoms. The aim of this study was to investigate the effect of a fixed combination of soy isoflavones on the oral bioavailability of levothyroxine in post-menopausal female volunteers.
12 healthy post-menopausal female, who were on stable oral levothyroxine as replacement/supplementation therapy for hypothyroidism, received a single recommended oral dose of a food supplement containing 60 mg of soy isoflavones (>19% genistin and daidzin) concomitantly with (test) and 6 h later (reference) the administration of levothyroxine in a randomized, open label, crossover fashion. Plasma concentrations of levothyroxine and soy isoflavones (daidzin, daidzein, genistin, genistein, S-equol) were determined by LC-MS/MS. Pharmacokinetic (PK) parameters were determined by non-compartmental analysis. No effect of soy isoflavones was assumed if the 90% confidence intervals (CIs) for the estimated ratio test/reference was included in the acceptance limits 0.80-1.25 for PK parameters Cmax and AUCt.
The test/reference ratios Cmax and AUCt of levothyroxine were very close to unity (1.02 and 0.99, respectively) and the corresponding 90% CIs (0.99-1.04 and 0.88-1.12, respectively) fell entirely within the acceptance bioequivalence limits.
The combination of soy isoflavones used in the present investigation does not affect the rate and extent of levothyroxine absorption when administered concomitantly in post-menopausal women.
因自身疾病接受左甲状腺素治疗的绝经后女性可能会同时服用含有大豆异黄酮的膳食补充剂来治疗绝经后症状。本研究的目的是调查固定剂量的大豆异黄酮组合对绝经后女性志愿者口服左甲状腺素生物利用度的影响。
12名健康的绝经后女性，她们正在接受稳定的口服左甲状腺素作为甲状腺功能减退的替代/补充治疗，以随机、开放标签、交叉方式，在服用含有60毫克大豆异黄酮（>19%染料木苷和大豆苷）的单一推荐口服剂量的食品补充剂的同时（试验组）以及6小时后（参照组）服用左甲状腺素。通过液相色谱-串联质谱法测定左甲状腺素和大豆异黄酮（大豆苷、大豆黄素、染料木苷、染料木黄酮、S-雌马酚）的血浆浓度。通过非房室分析确定药代动力学（PK）参数。如果PK参数Cmax和AUCt的估计比值试验组/参照组的90%置信区间（CIs）包含在接受限度0.80-1.25内，则认为大豆异黄酮无影响。
左甲状腺素的试验组/参照组比值Cmax和AUCt非常接近1（分别为1.02和0.99），相应的90% CIs（分别为0.99-1.04和0.88-1.12）完全落在接受生物等效性限度内。
本研究中使用的大豆异黄酮组合在绝经后女性中同时给药时，不会影响左甲状腺素的吸收速率和程度。
