辉瑞计划继续推进Remoxy临床开发

辉瑞（Pfizer）10月22日宣布，已实现与止痛药Remoxy（oxycodone，羟考酮）缓释胶囊生产相关的技术里程碑，该公司将继续推进Remoxy的开发项目。今年早些时候，辉瑞收到FDA的指导意见，该公司计划开展额外的临床研究及所要求的其他行动，以解决2011年6月收到的完整回应函（CRL）。

这些新的临床研究包括：一项关键的生物等效性研究，以弥补修改配方后的Remoxy与原配方的生物等效性相关临床数据，同时需要开展一项研究，分析修改配方后的Remoxy的潜在滥用性（abuse-potential）。正如此前所披露的，辉瑞计划于2015年中期提交完整的申请文件。

Remoxy是辉瑞于2011年耗资39亿美元收购King Pharmaceuticals后获得，但FDA出于对生产工艺和化学成分的担忧，分别于2008年和2011年拒绝了该药，这也给该药的前景蒙上了一层阴影。

今年5月，辉瑞称正在评估Remoxy项目的前景，称还未决定是否继续开发该药，使得合作伙伴Pain Therapeutics公司股价暴跌50%，业界曾担心辉瑞会放弃Remoxy的开发。

Remoxy是常见止痛药羟考酮（oxycodone）的凝胶胶囊，而羟考酮已被广泛滥用。Remoxy的凝胶配方使得难以通过压碎或与水或其他可溶物混合滥用。

英文原文：Pfizer commits to developing Pain Therapeutics' painkiller

(Reuters) - Pfizer Inc said it has decided to develop the abuse-resistant painkiller made by its partner Pain Therapeutics Inc, six months after the pharmaceutical giant's comments raised fears it would drop the drug.

Pain Therapeutics shares jumped as much as 30 percent in early trading on the Nasdaq.

The drug, Remoxy, has been rejected twice by the U.S. Food and Drug Administration due to concerns about its manufacturing process and chemical composition.

Pfizer said on May 10 that it had not decided whether to continue developing the drug, sending Pain Therapeutics shares crashing nearly 50 percent.

Pfizer will conduct new clinical trials to address the questions raised by the U.S. regulator, the company said on Tuesday.

The FDA had asked for two studies - one to show that a modified version of Remoxy was the bioequivalent of its original formulation, and another to investigate the potential for abuse of the modified version.

Remoxy is a gel-based capsule of the common painkiller oxycodone, which is widely abused. Remoxy's gel formulation makes it difficult to abuse by crushing or mixing with water or other solubles.

Drug abuse has become a growing concern in the United States and the FDA has already proposed stronger safety language on labels of opioids, a class of painkillers, in response to an epidemic of overdoses and deaths from these widely used medicines.

Opioids include formulations of morphine, oxycodone and fentanyl.

Remoxy was developed using the abuse-resistant technology of Durect Corp, whose shares jumped 11 percent to $1.56 on the Nasdaq.

Pfizer acquired the rights to Remoxy as a part of its acquisition of King Pharmaceuticals Inc in February 2011.

Shares of Pain Therapeutics were up 17 percent at $3.81 on the Nasdaq. Pfizer shares rose about 1 percent to $30.77 on the New York Stock Exchange.