New Delhi: What if the chemical signal your body produces after a hard workout could be taken as a pill instead? Scientists may be a step closer to finding out. US biotechnology company Enveda has reported that its experimental drug ENV-308 was well tolerated in a first Phase I trial involving 88 healthy adults.
The drug is designed to mimic Lac-Phe, a molecule that rises in the body after strenuous exercise and has been linked to reduced appetite.
The results do not show that ENV-308 can make people fitter or help them lose weight. The early-stage trial was designed mainly to assess safety. But it marks the first time a drug designed to mimic Lac-Phe has been tested in humans.
Lac-Phe, short for N-lactoyl-phenylalanine, came into focus after a 2022 study published in Nature.
Researchers found that levels of the molecule increased sharply after exercise in mice, racehorses and humans. When researchers gave Lac-Phe to mice with diet-induced obesity, the animals ate less and lost fat without becoming more physically active or burning more energy. Mice that were unable to produce Lac-Phe, meanwhile, ate more after exercising. The findings suggested that Lac-Phe could be one of the chemical signals through which exercise influences appetite.
That has made the molecule interesting to researchers looking for new approaches to obesity. Unlike GLP-1 drugs such as Wegovy and Zepbound, which act on hormone pathways involved in appetite and blood sugar regulation, ENV-308 is designed to imitate a signal generated by physical activity.
An early stage
Enveda says ENV-308 is intended to activate the same biological pathway as Lac-Phe. The company hopes the drug could eventually help people control their appetite and maintain weight loss.
But the latest results offer no evidence yet that it can do either in humans. Phase I trials are primarily intended to establish whether a drug is safe and tolerable and to determine how the body responds to different doses. Enveda’s results have not yet been published in a peer-reviewed scientific journal.
There is also a much bigger question—can one molecule reproduce any meaningful part of exercise’s effects? Exercise changes hundreds of processes across the body, affecting the heart, muscles, bones, metabolism, brain and immune system. Researchers have therefore spent years trying to develop “exercise mimetics” that reproduce specific effects rather than exercise as a whole. Lac-Phe is one of the more promising candidates because of its apparent role in appetite regulation. But ENV-308 is still at an early stage.
The next rounds of trials will need to establish whether the drug can actually reduce appetite or help people lose or maintain weight, and whether those effects are safe over longer periods. For now, the “exercise pill” remains an exciting possibility, not a replacement for exercise.
(Edited by Saptak Datta)