THE ARISING · Longevity & Healthspan
Sironax to Show Preclinical Data on NAD-Pathway Obesity Pill
Weight-loss drugs can shrink fat, but people often lose muscle along with it. According to its November 4 announcement, a company called Sironax claims that an experimental pill aimed at a cellular energy pathway produced preferential fat loss in preclinical findings.
According to Sironax's November 4 announcement, Sironax will present two posters on the drug, SIR4156, at ObesityWeek 2026. The Obesity Society's annual meeting runs Nov. 14–17 at the Gaylord National Resort and Convention Center in National Harbor, Maryland. Both posters are scheduled for Nov. 14, from 7:30 to 8:30 p.m. ET.
SIR4156 is described as a first-in-class, orally active allosteric activator of NAMPT. In plain terms, it is a pill meant to switch on an enzyme. NAMPT is part of the pathway that cells use to make NAD+, a molecule involved in producing energy.
One poster is titled Pharmacologic NAMPT Activation Improves Metabolism with Weight-Lowering Effects in DIO Mice. DIO stands for diet-induced obesity, meaning mice made obese through diet. The other poster is a weight-of-evidence carcinogenicity risk assessment of SIR4156 in obesity, which looks at cancer risk.
According to the report, the company claims its preclinical findings include preferential fat loss, lean-mass preservation, reduced muscle atrophy and improved physical performance. These are the company's own claims, from animal work.
Why this matters for people using GLP-1 drugs: weight lost on these medicines can include lean mass, which includes muscle. A drug that spared muscle could change what a good weight-loss result looks like. According to the report, Sironax is developing SIR4156 both on its own and in combination with incretins, the class that includes GLP-1 drugs.
The report gives no human efficacy data. It says Sironax has advanced enrollment in its Phase 2 FORGE-LM obesity trial of SIR4156. Results from mice have often failed to carry over to people, so the human trial is where the question gets tested.
Watch for what the posters show on Nov. 14, and for any results from the FORGE-LM trial.
SIR4156 remains investigational; its safety and efficacy in humans have not been established.