Pill aims to clear brain 'gunk' and reverse aging; RTR242 set for phase 1 trial in Australia

An experimental pill designed to clear toxic protein build-up in the brain and reverse brain aging is moving into human testing. Retro Biosciences said RTR242 will begin a Phase 1 study in Australia, with the first patient expected to receive the treatment by the end of 2025. Backed by Sam Altman, the company aims to add a decade of healthy life by reviving the brain’s cellular cleaning system.

RTR242 works by reactivating autophagy, the cell’s housekeeping mechanism that breaks down damaged components and misfolded proteins such as tau and amyloid beta. In healthy brains, autophagy helps clear cellular debris; in neurodegenerative diseases, the system often slows or stalls, allowing toxic protein clumps to accumulate and impair neurons. The pill is designed to restart autophagy and enable affected cells to clear the toxic buildup, potentially restoring function rather than merely slowing decline. The approach differs from recently approved Alzheimer’s drugs that target amyloid plaques to slow symptoms.

Joe Betts-LaCroix, chief executive officer of Retro Biosciences, argues that while curing cancer or heart disease could extend life by a few years, adding 10 years of healthy lifespan would be a more transformative achievement. He has described the firm’s mission as trying to reset aspects of biology to a younger state, rather than simply extending expectations.

The company notes the broader context of neurodegenerative disease dollars and patient numbers. About 7 million Americans live with Alzheimer’s disease today, a figure expected to rise toward 13 million by 2050 as the population ages. Parkinson’s disease affects about 1 million Americans, with roughly 90,000 new diagnoses each year; projections show the PD population climbing to about 1.2 million by 2030. Retro Biosciences says its Australian Phase 1 trial is a necessary step toward larger studies and a potential $1 billion Series A round to fund further development.

Preclinical data for RTR242 has not been released publicly. The company says the pill targets living but dysfunctional cells that are clogged with toxic, misfolded proteins. By kickstarting autophagy, the therapy aims to clear the waste that can undermine cellular health and help neurons survive longer.

The strategy stands in contrast to some Alzheimer's drugs that aim to remove amyloid plaques to slow cognitive decline. Betts-LaCroix has framed Retro’s approach as more ambitious, saying: 'Adding 10 years of healthy lifespan to adults will be one of healthcare’s greatest achievements.'

The scope of neurodegenerative disease burden has been underscored by public interest in cases such as Wendy Williams, diagnosed with frontotemporal dementia in 2023, and Bruce Willis, who disclosed a frontotemporal dementia diagnosis in the same year. While celebrity cases receive attention, experts say the overall health impact is the driving factor for research investments in this area.

The Australian Phase 1 study will evaluate safety and dosing, while researchers monitor biomarkers of autophagy and brain function. If early results are favorable, Retro plans expanded trials to determine whether RTR242 can meaningfully reverse aspects of brain aging and improve function in patients with neurodegenerative disease. The company has signaled that positive data could accelerate its fundraising goals and its push toward broader, longer trials.

Retro’s leadership emphasizes a longer-term objective: preserve health and vitality well into old age by rebooting the brain’s natural cleanup system. The company has argued that achieving a decade of healthy life would represent a milestone in modern medicine, potentially redefining how aging and neurodegenerative disease are treated.