Insilico Medicine researchers revealed that their AI-designed drug candidate rentosertib reduced biological age across six proteomic aging clocks during a Phase IIa clinical trial for idiopathic pulmonary fibrosis. Published in Nature Biotechnology, the findings demonstrate a reversal of biological age.
A therapeutic molecule discovered and designed through artificial intelligence has demonstrated a capability in clinical testing: it lowered the biological age of patients over a twelve-week treatment period. The compound, known as rentosertib, stems from the development pipeline of Insilico Medicine, an AI drug discovery and development company. While created to target chronic lung disease and extend patient lifespan, the drug’s evaluation has opened a new avenue for assessing geroprotective therapies in standard human trials.
From Target Discovery to Clinical Testing in Idiopathic Pulmonary Fibrosis
The underlying research originated from a Phase IIa randomized, double-blind, placebo-controlled trial (NCT05938920) conducted across 21 locations in China. The trial enrolled male and female patients older than 40 years with a confirmed diagnosis of idiopathic pulmonary fibrosis (IPF) in stable condition. Out of 128 screened participants, 71 were selected to receive either 30 mg of rentosertib once daily, 30 mg twice daily, 60 mg once daily, or a placebo.
Unlike traditional geroscience efforts that rely on repurposing generic drugs like metformin or rapamycin, Insilico incorporated aging biology into its discovery strategy from the start. Using an AI-powered target discovery platform, researchers identified TNIK as a novel target implicated in both aging and fibrosis. The company’s generative chemistry platform then designed rentosertib to engage that target, progressing from initial target identification to a preclinical candidate in roughly 18 months.
Tracking Biological Shifts Through Six Proteomic Aging Clocks
To evaluate how the drug affected cellular aging, an international team of scientists analyzed longitudinal serum proteomic data collected during the trial. Researchers evaluated six published proteomic aging clocks on baseline and follow-up samples from a subset of 42 Asian participants with a mean age of 67.1 years.
The evaluation incorporated four chronological clocks alongside two mortality-based models. Although these tools rely on different training objectives and methodologies, all six models consistently indicated a reduction in predicted biological age among patients treated with rentosertib compared to those receiving a placebo.
“The drug may modulate complementary dimensions of biological aging.”
Insilico Medicine researchers, via Gizmodo
Reversal Peaks at Week Four
The magnitude of age reversal varied across dosage regimens and evaluation timepoints. Treatment arms showed consistent reductions in biological age relative to baseline, whereas placebo recipients experienced minimal change or slight increases over the 12-week span.
Statistical significance concentrated heavily at the four-week mark. Participants in the 30 mg twice-daily group experienced an estimated biological age reversal of approximately three to four years, with certain clocks registering up to a six-year reduction. Researchers confirmed that these shifts far exceeded chance expectations via permutation testing with patient-level label shuffling.
Longevity Markers and Respiratory Function
A critical observation from the trial involved the relationship between lung capacity and biological age. Forced Vital Capacity (FVC), the standard physiological measure of lung function that typically declines with age and disease progression, showed promising dose-dependent improvements in treated patients.
In the 60 mg once-daily group, patients experienced a mean improvement in forced vital capacity of +98.4 mL, contrasted against a mean decline of -20.3 mL in the placebo group.
The publication of these findings in Nature Biotechnology establishes a proof-of-concept framework for integrating aging biomarkers into standard clinical trials. By demonstrating that an AI-designed molecule can simultaneously address a specific chronic pathology and modulate systemic proteomic aging clocks, the study points toward a faster discovery pipeline for longevity therapeutics.
Despite the promising early data, rentosertib remains far from commercial availability or regulatory approval. The compound must clear extensive subsequent clinical evaluations before any definitive claims regarding human lifespan extension can be established.
