As market declines, Purdue hopes to kick opiate habit

Purdue Pharma is becoming increasingly reluctant to develop new opioids, and is diversifying following FDA approval of a drug used to treat constipation associated with the painkillers.

In an interview with pharmaphorum after the FDA approved the company’s Simproic (naldemedine), executives said the company is evaluating new forms of painkillers, although it has not written off development of new opioids.

Purdue is one of a group of companies under fire for producing prescription opioid painkillers, at a time when addiction to them has reached epidemic proportions in the US.

The Department of Health and Human Services estimates that the number of deaths due to opioid overdoses has quadrupled since 1999, with a further cost of $55 billion in health and social costs from abuse of the drugs every year.

The companies face a range of allegations saying they haven't done enough to stop abuse of the drugs. Purdue is facing a lawsuit raised by the city of Everett in Seattle, which alleges the company allowed its opioid painkiller OxyContin (oxycodone) to be "funnelled through the black market" and thereby fuel an opioid crisis in the city.

Purdue has asked the court to dismiss the lawsuit, but the legal challenge only emphasises how difficult the market has become.

David Saussy, head of scientific evaluation at the North Carolina-based firm, said the firm is "agnostic" about developing new opioids but only where they offer "benefits compared with what is already on the market.”

The company says it is now focused on developing painkillers that have different mechanisms of action and are less likely to be abused, said Saussy.

For instance, in December Purdue signed an agreement with AnaBios to develop non-opiate, painkiller drug candidates using the sodium ion channel.

Saussy said: “If you look at the market as a whole, (opiate) prescriptions are down. The market is declining and a number of products are going off patent in the next five or 10 years.”

The US Drug Enforcement Administration said the amount of opioid medications that can be manufactured for sale and research will be cut by 25% this year, because of the concerns about abuse potential.

Purdue's extended release OxyContin formulation is harder to crush and abuse and has patent protection until 2025, after the FDA prevented generic cheap generic competition in 2013 to prevent the market being flooded with cheap painkillers.

The future of the painkiller market will likely be based around products “that offer patients better treatment outside the opiate space,” said Saussy.

Purdue’s latest FDA-approved drug is not even a painkiller, but Symproic (naldemedine), a pill approved for opioid-induced constipation in adults with chronic non-cancer pain.

Purdue will co-market the drug with Japan's Shinogi, having established an alliance with the firm in December.

The company wouldn’t give sales estimates, but firm expects the product to do “very well” in a market worth around $2 billion. It points to clinical data suggesting it allows patients to have more complete bowel movements than already marketed rivals.

There is also the potential to steal painkiller sales from Endo, whose rival painkiller Opana ER has an uncertain future because of the FDA's concern about its addictive potential.

Purdue will closely watch for an FDA decision, after a panel of its advisers recently  said the benefits of Opana ER no longer outweigh its risks, because of concerns about its abuse-deterrent properties.

The company pointed out that the FDA’s concerns were limited only to Opana, and not OxyContin or any other opioid painkiller.

The FDA could remove Opana ER from the market, or require heavy safety warnings on labelling – which could benefit sales of rival products from Purdue and others.

Purdue's ability to co-market OxyContin with a product that could help with any constipation could give a further advantage over Endo if Opana ER stays on the market.

“We are waiting to hear how the FDA will respond to (the panel),” said head of medical affairs strategic research, Tracy Mayne.