Lilly's experimental oral obesity drug, aleniglipron, helped patients lose up to 12.1% of their body weight in 36 weeks. Study completion rates were nearly identical to placebo, indicating high tolerability, according to Nature. Aleniglipron's ability to help patients lose up to 12.1% of their body weight in 36 weeks, with study completion rates nearly identical to placebo, positions it as a contender in the obesity treatment market.
Lilly is advancing this oral GLP-1, showing strong tolerability and significant weight loss. However, its more potent injectable drug, retatrutide, offering even greater weight loss, has surfaced a concerning neurological side effect.
The future of the obesity drug market will likely be defined by a strategic balance between maximal weight loss and an acceptable safety profile. Oral options could broaden market access despite slightly lower efficacy.
What We Know About Lilly's Next-Gen Obesity Drugs
Lilly's aleniglipron, an oral GLP-1, reduced body weight by up to 12.1% at 36 weeks (120 mg dose vs. 0.8% for placebo), according to Nature. Its study completion rates (73.3% to 78.1%) mirrored placebo (75.0%).
In contrast, Lilly's injectable retatrutide achieved 28.3% weight loss over 80 weeks in the Phase 3 TRIUMPH-1 study for obese patients without diabetes, and 26.6% placebo-adjusted weight loss at 68 weeks in TRIUMPH-4 for obese or overweight patients with knee osteoarthritis, per StatNews. However, TRIUMPH-4 also reported dysesthesia, a neurological signal, in over 20% of patients on the 20-mg retatrutide dose, with rates increasing at higher doses. The stark difference between retatrutide's 28.3% weight loss and the dysesthesia signal in over 20% of patients suggests a fundamental trade-off between maximal efficacy and patient safety.
For context, Novo's CagriSema showed a 23% average body weight loss at 84 weeks in the REDEFINE-4 study, as reported by Business Standard.
