FDA move gives Purdue edge in painkiller market

FDA move gives Purdue edge in painkiller market
FDA move gives Purdue edge in painkiller market

The FDA's decision to allow a generic version of Endo's original Opana ER (oxymorphone hydrochloride) is forcing the company to rejigger its financial outlook. The company said in a statement Friday that it has based projections “on an assumption the FDA would remove generic versions of Opana ER from the market by mid-year.” Such a move could have helped the drug maker recoup some lost ground—sales of its Opana ER were $56 million for the quarter ended March 31, a 31% drop from the same period last year, when sales were $81 million.

Friday's decision also gives Purdue Pharma an edge—the FDA approved the drug maker's petition to bar generics of OxyContin (oxycodone hydrochloride) last month. FDA said it supported banning non-tamper-proofed generic oxycodone hydrochlorides, which are easier to abuse than the reformulated version, and “determined that reformulated OxyContin can be expected to make abuse by injection difficult” and is expected “to reduce abuse by snorting compared to original OxyContin.”

The painkiller industry has been subject to scrutiny for a number of reasons, including accusations that pain pill advocacy groups and drug makers funded misleading physician and patient materials. Fueling concerns is the sheer volume of abuse: the latest Centers for Disease Control stats show the number of opioid prescriptions have increased at retail pharmacies by almost 200% between 1991 and 2011, and the number of deaths associated with opioid analgesics climbed from around 4,000 in 1999 to around 17,500 in 2011. The agency's data also indicates that in 2010 2 million people reported using prescription painkillers for non-medical reasons for the first time. CDC says most painkiller prescriptions come from primary care physicians and internists rather than specialists.

This latest move, however, is a new one: FDA issued pain pill draft guidance in January that indicated criteria the regulator will use to determine if a newer version of a painkiller may be less subject to abuse than an older version. The regulator's A to B comparisons include: how much easier (or harder) it is to break down the newer, abuse-deterrent version from the original; comparing the pharmokinetic profiles of the two versions; and the abuse potential.

“The extent to which an abuse-deterrent product is able to reduce abuse will never be absolute,” the regulator noted in the January draft guidelines. FDA said that this limitation makes comparing iterations its only means for assessing what constitutes abuse deterrence.

In Purdue's case, the FDA determined the latter formulation was harder to crush, break or dissolve, and was harder to convert into an injectible gel than the 1995 model. The regulator also said in April that while the new formula will be harder to inject or snort than original OxyContin, it could still be abused.

The FDA's write-up of Endo's efforts indicate the drug maker failed to hit similar marks—the regulator's assessment indicated that the new Opana ER is indeed harder to crush than the first version, but studies submitted with its anti-generic petition showed the treatment could be “subjected to other forms of manipulation, such as cutting, grinding, or chewing.” The regulator also said Endo's candidate “can be readily prepared for injection, despite Endo's claims that these tablets have ‘resistance to aqueous extraction,'” and that the drug can be snorted using easy-to-obtain tools.