Orexigen Therapeutics, Inc. has announced that the results of its IGNITE study were published online by Obesity, the peer-reviewed journal of The Obesity Society. The IGNITE study was an open-label randomized Phase 3b study designed to evaluate the use of Contrave in combination with a commercially-available comprehensive lifestyle intervention program compared with usual care in a real-world weight-loss setting. Study results showed that treatment with Contrave, when used in a manner consistent with prescribing information in the U.S. and EU, resulted in a significant decrease in body weight compared with usual care.

"The IGNITE study findings, which are consistent with results from our four previous Phase 3 trials in more than 4,500 patients, build on our clinical experience with Contrave in a real-world setting," said Peter Flynn, Ph.D., Senior Vice President, Head of Development, Regulatory Affairs and Safety at Orexigen. "The study findings demonstrate the significant weight loss and associated benefits that can be achieved by combining Contrave with appropriate diet and exercise lifestyle modification. We believe Contrave may be a valuable addition to a weight loss regimen for many individuals attempting to lose weight with diet and exercise."

IGNITE study design and results

The open-label, post-marketing IGNITE trial evaluated 242 obese (body mass index [BMI] 30-45 kg/m2) or overweight (BMI 27-45 kg/m2) adult patients ages 18 to 60 with dyslipidemia and/or controlled hypertension. During an initial 26-week controlled treatment phase, patients were randomized to receive either Contrave in combination with a commercially-available comprehensive lifestyle intervention program (a telephone- and internet-based program that included a nutrition and exercise program with individualized goal setting) or usual care (standard diet and exercise advice from the study site). At week 16, participants receiving Contrave had to achieve at least 5 percent weight loss to continue therapy, consistent with U.S. and EU prescribing information. The primary endpoint of the study was the percent change in body weight per protocol population; secondary endpoints included the percentage of patients achieving a loss of at least 5 percent, 10 percent or 15 percent of baseline body weight.

At 26 weeks, results showed that:

Per protocol population, study participants treated with Contrave lost significantly more weight than usual care participants (9.5 percent vs. 0.9 percent (p<0.0001)).

Significantly more Contrave-treated patients achieved three weight loss thresholds than usual care-treated patients:

5 percent vs. 12.2 percent had ≥5 percent weight loss (p< 0.0001)

3 percent vs. 3.7 percent had ≥10 percent weight loss (p<0.0001)

7 percent vs. 0 percent had ≥15 percent weight loss (p value not determined)

Significantly greater reductions in obesity-related risk factors were also observed in Contrave-treated participants compared with those treated with usual care, including triglycerides, waist circumference, glucose, insulin and a measure of insulin resistance.  Contrave-treated participants also experienced a significantly greater increase in high density lipoprotein (HDL or "good") cholesterol.

At week 26, participants in the usual care group transitioned to treatment with Contrave and the comprehensive lifestyle modification program. All continuing participants were followed through week 78, a longer duration than previous Phase 3 clinical trials of Contrave, which lasted 56 weeks. Participants who remained on Contrave through 78 weeks generally maintained the initial weight loss seen at 26 weeks. Additionally, participants who began treatment with Contrave at week 26 experienced similar weight loss as those initially randomized to treatment with Contrave.

Overall, Contrave was well tolerated with a safety profile consistent with prior studies. The most common adverse event was nausea, leading to withdrawal in 7 percent of study participants.  No adverse events that led to discontinuation of Contrave had an onset date after the initial 26 week treatment period.