Yesterday, Merck (MRK) updated the status of two of its pipeline candidates, both used to treat migraine. While the company abandoned MK-3207, it will continue to develop telcagepant (MK-0974). Although MK-3207 was found to be effective, it caused liver abnormalities in some patients on discontinuing the drug. Due to this, Merck has decided to abandon any further studies of the drug.

The phase III trial conducted by Merck for telcagepant found it to be more effective than placebo for acute treatment of multiple migraine attacks. In another study, the safety of the product was compared to another migraine drug of Merck, Maxalt (rizatriptan). The company presented data from both trials at the International Headache Congress and plans to initiate discussions regarding the next steps with the US Food and Drug Administration (FDA) later this year.

The telcagepant trial was carried out on 1677 patients who experienced at least one moderate or severe migraine attack. Telcagepant tablets at doses of either 140 mg or 280 mg or placebo were used to treat up to four acute migraine attacks. The efficacy of the treatment was assessed by analyzing pain freedom, pain relief/reduction and absence of migraine-associated symptoms (nausea and sensitivity to light and sound) for two hours after treatment and sustained pain freedom from two to 24 hours after treatment. Both doses of the drug were found to be more effective than placebo.

Another trial to ensure the safety of telcagepant tablets was carried out on patients who took either the drug or rizatriptan. The primary endpoint of the study was the proportion of patients with at least one pre-specified adverse event such as chest pain, chest tightness, asthenia, paraesthesia, dysaesthesia or hyperaesthesia. Significantly fewer patients treated with telcagepant reported at least one pre-specified adverse event compared with those treated with rizatriptan.

The failure of MK-3207 is the latest in a series of pipeline setbacks experienced by Merck over the past few quarters. In June rolofylline, Merck’s heart failure drug failed to meet its primary endpoint in a late stage study. In October last year the company ended development of its obesity drug taranabant, which was in phase III development. We have a Neutral recommendation on the stock.
Read the full analyst report on “MRK”
Zacks Investment Research