Altimmune, Inc. announced topline results from a Week 24 interim analysis of 160 subjects in its 48-week MOMENTUM Phase 2 obesity trial of pemvidutide along with the results of the 12-week Phase 1b safety trial of pemvidutide in subjects with obesity or overweight and type 2 diabetes. The MOMENTUM Phase 2 obesity trial is being conducted at 30 sites across the U.S., with Dr. Louis Aronne, Professor of Metabolic Research and Professor of Clinical Medicine, Weill Cornell Medicine, a leading authority in obesity and obesity clinical trials, serving as the Principal Investigator. The trial was designed to enroll approximately 320 subjects with obesity or overweight with at least one co-morbidity and without diabetes.

Subjects were randomized 1:1:1:1 to 1.2 mg, 1.8 mg, 2.4 mg pemvidutide or placebo administered weekly for 48 weeks in conjunction with diet and exercise. A pre-specified interim analysis was conducted after 160 subjects completed 24 weeks of treatment. Subjects in the interim analysis had a demographic composition similar to the full study population previously announced, with a median age of approximately 48 years, a median body mass index of approximately 36 kg/m2, and a median body weight of approximately 100 kg.

Approximately 75% of subjects were female, and approximately 20% of subjects were of Hispanic ethnicity. At Week 24, subjects receiving pemvidutide achieved mean weight losses of 7.3%, 9.4% and 10.7% at the 1.2 mg, 1.8 mg, and 2.4 mg doses, respectively, with the placebo group experiencing a mean weight loss of 1.0% (p < 0.001 at all three doses vs placebo, efficacy estimand using a mixed model of repeated measures [MMRM] analysis). An impact of baseline body weight was observed, where subjects with baseline body weight less than or equal to 115 kg (75% of the study population) achieved mean weight losses of 8.2%, 10.6%, 11.9% and 0.8% at the 1.2 mg, 1.8 mg, 2.4 mg and placebo groups, respectively (p < 0.001 at all three doses vs placebo).

Approximately 50% of subjects achieved 10% or more weight loss and approximately 20% of subjects achieved 15% or more weight loss at Week 24 at the 1.8 mg and 2.4 mg doses. Robust reductions in waist circumference (a measure of visceral fat) and serum lipids were also observed, and clinically meaningful reductions in blood pressure were achieved without meaningful increases in heart rate. Glucose homeostasis was also maintained, with no significant changes in fasting glucose or HbA1c.

Regarding safety, upper GI events of nausea and vomiting comprised the majority of AEs. These events were predominantly mild and moderate in severity, dose-related and similar in frequency to those observed in prior trials of pemvidutide. Rates of lower GI AEs including diarrhea and constipation were notably low.

This AE profile was observed in the absence of dose titration at the 1.2 mg and 1.8 mg doses and with a limited 4-week dose titration at the 2.4 mg dose. One subject (2.4%) experienced a serious adverse event of nausea and vomiting requiring rehydration at the 2.4 mg dose. Treatment discontinuation rates were 28.2% in subjects receiving placebo and 24.0% in subjects receiving pemvidutide.

The majority of placebo discontinuations were due to withdrawal of consent, while approximately half of the withdrawals across the pemvidutide dose groups were attributed to GI AEs. These discontinuations occurred almost entirely in the first 16 weeks of treatment. The protocol did not allow for dose reduction due to intolerability as employed in other incretin trials.

The Phase 1b trial, which was conducted to evaluate the safety profile of pemvidutide in subjects with overweight or obesity and type 2 diabetes, was comprised of 54 subjects randomized 1:1:1:1 to 1.2 mg, 1.8 mg, 2.4 mg pemvidutide or placebo administered weekly for 12 weeks. No caloric restrictions or lifestyle interventions were employed. Subjects were required to be 18-65 years of age with BMI = 28 kg/m2 and type 2 diabetes on a stable regimen of diet and exercise, metformin with absent or mild GI symptoms, or SGLT-2 therapy for at least 3 months.

Subjects receiving pemvidutide achieved mean weight losses of 4.4%, 6.1% and 7.7% at the 1.2 mg, 1.8 mg, and 2.4 mg doses, respectively, over only 12 weeks of treatment, with the placebo group experiencing a mean weight gain of 0.8% (efficacy estimand using MMRM analysis). Glucose homeostasis was maintained throughout the 12 weeks of treatment, with no significant changes in fasting glucose or HbA1c and no hyperglycemic AEs. No SAEs were observed in patients treated with pemvidutide.

Rates of GI AEs were low, and there were no AEs leading to study discontinuation. Pemvidutide is a novel, investigational, peptide-based GLP-1/glucagon dual receptor agonist in development for the treatment of obesity and NASH. Activation of the GLP-1 and glucagon receptors is believed to mimic the complementary effects of diet and exercise on weight loss, with GLP-1 suppressing appetite and glucagon increasing energy expenditure.

Glucagon is also recognized as having direct effects on hepatic fat metabolism, leading to rapid reductions in levels of liver fat. Pemvidutide incorporates the EuPort™ domain, a proprietary technology that increases its serum half-life for weekly dosing while likely slowing the entry of pemvidutide into the bloodstream, which may improve its tolerability.