Progenics Pharmaceuticals Inc. stands to collect $50 million, CEO Mark Baker told BioWorld Today, thanks to approval by the FDA of oral Relistor (methylnaltrexone bromide), partnered with Valeant Pharmaceuticals International Inc. for opioid-induced constipation (OIC) in adults with chronic noncancer pain. He called the approval "a great milestone for us and a great development for patients." His firm also gets 15 percent to 19 percent tiered royalties in the U.S., resetting annually, and 60 percent of profits outside.

Shares of Tarrytown, N.Y.-based Progenics (NASDAQ:PGNX) closed at $6.14, up $1.20, or 24.3 percent.

Relistor has been available since 2008 in subcutaneous form, and the oral version – 450-mg tablets once daily – will compete with London-based Astrazeneca plc's Movantik (naloxegol) tablets. Progenics licensed Relistor rights originally to Raleigh, N.C.-based Salix Pharmaceuticals Inc., which was later acquired by Valeant, of Laval, Quebec, in an $11.1 billion deal. (See BioWorld Today, March 17, 2015.)

"We have a two-horse race here," Baker said. Relistor, like Movantik, targets the mu opioid receptor, "which is where this problem has been created," he said. "We'll see in the marketplace what aspects are appealing to the patients and to the payers. Typically, these markets split 60-40, 65-35. Why do we think Relistor may be the stronger competitor? An important thing in our mind is the speed of onset of action with Relistor. If you're a person suffering from constipation, this is high on your list." No specific treatments for OIC that address the underlying cause have been approved, "so people have been using over-the-counter laxatives for lack of anything better," he said. "The laxatives have just not been that effective."

For Movantik, Astrazeneca has a co-commercialization agreement with Daiichi Sankyo Co. Ltd., of Tokyo, in the U.S., under which Daiichi provided $200 million up front plus sales-related payments of up to $625 million. The firms have been doing much to promote Movantik, "including a disease-awareness ad that was on the last Super Bowl," Baker said. "We expect that Valeant will make similar efforts, in addition to the efforts they have been making in selling the subcutaneous" Relistor. The Super Bowl ad drew some fire from politicos and in social media, where some claimed it encouraged the use of opioids.

Brean Capital analyst Jonathan Aschoff said his firm "believes[s] that oral Relistor will see significant uptake because it can be used on a pro re nata [as needed] schedule, due to its more rapid, predictable onset of action. Predictability is important for constipation drugs." In a research report, he noted that Progenics would get one-time milestones of $10 million, $15 million, $20 million, $30 million, $50 million, and $75 million that will be triggered by minimum calendar year Relistor sales of $100 million, $150 million, $200 million, $300 million, $750 million, and $1 billion, respectively. "We believe that all but the last milestone will all be achieved by 2020, and have modeled the first two in 2017, the next two in 2018, and the fifth in 2020," Aschoff said, hailing the "backed-up" FDA for "finally" understanding the oral-Relistor need.

Jefferies analyst Gena Wang said her firm's due diligence with key opinion leaders suggests a large opportunity. "The target market for the peripherally acting mu opioid receptor antagonists could be about one million OIC patients in the chronic non-cancer pain setting," she estimated in a report, and efforts by Astrazeneca/Daiichi to broaden sales among primary-care physicians who write about 50 percent of opioid prescriptions should "pave the way for the upcoming oral Relistor launch. In the worst-case scenario, where Valeant fails to fulfill its launch obligation (specific number of sales reps and their incentive package[s]), Progenics still could exercise the right to retrieve the asset," she noted.

RBC Capital Markets analyst Douglas Miehm looked on the brighter side. "We anticipate that [Valeant's] shares will see strength following the oral Relistor approval and the FDA's Dermatologic and Ophthalmic Drugs Advisory Committee vote to support the approval of brodalumab ahead of its Nov. 16, 2016 PDUFA date," he said in a report. Shares of Valeant (NYSE:VRX) closed Wednesday at $24.57, up $1.02. The FDA panel balloted 18-0 in favor of approving the BLA for brodalumab, branded Siliq, to treat adults with moderate to severe plaque psoriasis. Brodalumab targets the interleukin-17 receptor. (See BioWorld Today, July 20, 2016.)