By Lisa LaMotta Sep 21, 2010 1:45 pm

Less than a week after Arena’s lorcaserin wasn’t recommended for approval, the competition has released new data to support its own obesity treatment.

Less than a week after Arena Pharmaceuticals’ (ARNA) diet pill lorcaserin wasn’t recommended for approval by a panel of experts, the competition has released new data to support its own obesity treatment.

Vivus (VVUS) announced Tuesday morning the results for a two-year study of the obesity drug Qnexa. The study, called Sequel, was a follow-up to the original one-year Conquer study. Sequel followed all of the 675 patients who completed the first 56 weeks for another 52 weeks. The results of the study affirmed that Qnexa is an effective weight-loss treatment and may even point to it being safer than it previously appeared.

Sequel showed that patients taking the high dose of Qnexa achieved and maintained weight loss of 11.4%, about 26 pounds, throughout the two years, while placebo patients only achieved about 2.5% weight loss. Patients were kept in the groups that they were originally randomized to in the first year. Beyond the solid efficacy data, the Sequel study showed that patients without diabetes were 76% less likely to develop the condition on the top dose of Qnexa. Patients also saw improvements in weight-related co-morbidities like hypertension.

“Overall, we believe the data add to the strong efficacy evidence and demonstrates continued positive risk/benefit profile of the drug,” wrote Leerink Swann analyst Steve Yoo in a note to investors on Tuesday. “We are especially heartened by the lower relative risk of the serious vascular events.”

While this is all positive news for Vivus and Qnexa, it might not be enough to sway the FDA to a decision of approval. Obesity drugs have been a bit of a thorn in the side of the agency — no treatments to date have been without their problems. The FDA has been forced to revisit or withdraw several diet pills over the years that have caused serious safety problems. The current administration of the agency is being extra cautious about approving this class of drugs.

An advisory committee in June voted against recommending Qnexa for approval in a close vote. The panel was never concerned about the efficacy of the drug like it had been recently with Arena’s lorcaserin, but there were safety concerns. The two biggest brought up by the panel were cardiovascular risks and teratogenicity.

Qnexa is a combination of two drugs, phentermine and topiramate, at lower doses. Both drugs have been on the market for other indications. Phentermine was the non-lethal portion of the Fen-Phen combination and topiramate is marketed by Johnson & Johnson (JNJ) for seizures under the brand name Topamax.

The concerns that came out of the Vivus panel had more to do with the issues that presented themselves with the previous iterations of the drug than with Qnexa. Phentermine is known to raise the heart rate, but the data presented throughout the Qnexa studies (including Sequel) showed that the weight-loss drug only modestly raised the heart rate of patients. Meanwhile, the concerns about Qnexa causing issues during pregnancy are also related to the issues presented at the higher dosages in Topamax — which has been shown to cause birth defects. There was no evidence of birth defects or problem pregnancies in the women who became pregnant during the Qnexa trials.

Ultimately, the panel was most concerned that there wasn’t enough data to allay fears about these two issues. A two-year study could help ease the concerns of the FDA, but it might not be for a long enough period of time (five years could be preferable to the agency) or include enough patients (thousands would be better than hundreds) to benefit Vivus.

The FDA is set to make its decision on the approvability of Qnexa by Oct. 28. While it usually follows the decision of its panels, it’s not required to. It’s still likely that the FDA will reject Qnexa and issue a Complete Response Letter to Vivus, but the new two-year data could be solid grounds for the company’s resubmission of its New Drug Application later this year.