In June, the Concord, Mass.–based company Tremeau Pharmaceuticals announced that the Food and Drug Administration was letting it proceed with a phase 3 clinical trial to test rofecoxib, the once-bestselling painkiller known as Vioxx, in patients with migraine.
The anti-inflammatory drug, a cyclooxygenase-2 (COX-2) inhibitor, received its first FDA approval in 1999 and became widely prescribed for arthritis and acute pain. In 2004 it was withdrawn by its manufacturer, Merck, after being shown to raise the risk of cardiovascular events.
In clinical trials and in real-world epidemiological studies, rofecoxib was associated with elevated heart attack, stroke, and related deaths; one 2005 study estimated that it had been responsible for some 38,000 excess deaths in the United States before being withdrawn. In 2007 Merck, beset with allegations that it had suppressed and mischaracterized rofecoxib’s safety data, paid out nearly $5 billion to settle thousands of lawsuits filed by patients and their families.
, an indication for which it received an orphan drug designation in 2017 and the agency’s green light for trials in 2020.
Brad Sippy, Tremeau’s chief executive officer, said that his company chose the two indications in part because both patient populations have low cardiovascular risk. Migraine patients are generally younger than the arthritis populations formerly treated with rofecoxib and are unlikely to take the drug for more than a day or 2 at time, avoiding the risks associated with extended exposure.
A crowded market
The past several years have seen the emergence of a cornucopia of new migraine treatments, including monoclonal antibodies such as erenumab (Aimovig, Amgen), which help prevent attacks by blocking the vasodilator calcitonin gene-related peptide, or CGRP. In addition to the standard arsenal of triptans and nonsteroidal anti-inflammatory drugs for acute pain relief, migraine patients can now choose among serotonin-blocking agents such as lasmiditan (Reyvow, Eli Lilly), known as “ditans,” and small-molecule CGRP antagonists such as ubrogepant (Ubrelvy, Abbie), known as “gepants.” Some NSAIDs, including one COX inhibitor, have been formulated into rapidly absorbed powders or liquids for migraine.
Mr. Sippy said he sees a role for rofecoxib even in this crowded space. “Migraine as you know is a multimodal situation – few people say that only one drug works for them,” he said. “We think this is an option that would basically be like a high dose of ibuprofen,” but with less frequent dosing and lower gastrointestinal and platelet effects compared with ibuprofen and other NSAIDs.
An improved formulation
Rofecoxib “crosses the blood brain barrier very readily – better than other COX inhibitors on the market,” Mr. Sippy added. “It was well absorbed in its original formulation, and our product is even better absorbed than the original – we estimate it’s probably an hour quicker to [peak concentration].” In addition, he said, “our formulation is more efficient at delivering the drug so we don’t need as much active ingredient – our 17.5 milligrams gets you the same systemic exposure as 25 milligrams of the old product.”