Cerevance's non-dopamine Parkinson's pill solengepras meets Phase 3 goal on off time

Cerevance, a privately held biotech based in Boston, reported on 7 October 2026 that its once-daily oral Parkinson's drug solengepras met the primary endpoint of a Phase 3 trial as an add-on to levodopa ¹². The company now plans to take the data to the FDA to settle the next steps for the drug ¹.

What the trial found

The study randomised 341 people whose motor symptoms still fluctuated despite levodopa and other treatment to placebo, 75 mg or 150 mg of solengepras, taken once a day for 12 weeks ². At entry, participants averaged 5.65 hours a day of off time, meaning periods when medication wears off and symptoms return or worsen ¹.

At the 150 mg dose, average daily off time fell by 0.61 hours more than with placebo at week 12, and the gap was visible from week 2 ². On time, the key secondary measure, rose by 0.60 hours against placebo at that dose without the troublesome dyskinesia that interferes with daily life ¹. BioPharma Dive reported that this result was only just statistically significant ¹. The sources give no efficacy figures for the 75 mg arm.

Cerevance also reported gains beyond motor control in the 150 mg group: a 1.91-point improvement on a Parkinson's rating scale of daily living and a 0.98-point improvement in daytime sleepiness, both against placebo ². The company described the drug as generally well tolerated, with most adverse events mild or moderate. Headache, urinary tract infection, insomnia and nausea were the most common in the higher-dose arm, and that arm had no serious adverse events ¹.

Solengepras works differently from most Parkinson's medicines, which raise or protect dopamine. It is an inverse agonist of GPR6, a receptor concentrated in dopamine-expressing neurons, and it is meant to damp the overactive indirect basal ganglia pathway that acts as a brake on movement once dopamine is lost ². Cerevance hopes that by leaving dopamine alone it can improve movement while avoiding the involuntary movements that levodopa often causes ¹.

What it means for the market

The result keeps a first-in-class, non-dopaminergic mechanism alive in a field dominated by levodopa and other dopamine-based drugs ². That matters for neurology developers and for any company weighing partnerships in Parkinson's, an area Fierce Biotech describes as busy with deals: Genentech paid Alector $100 million for an enzyme replacement therapy earlier that week, and AbbVie won FDA approval for tavapadon, the drug at the centre of its $8.7 billion purchase of Cerevel Therapeutics, the month before ².

The trial also rescues a programme that looked weaker in April 2025, when solengepras given alone to untreated patients was no better than placebo on a Parkinson's disease scale at 12 weeks ². The new data come from a different setting, as an add-on in patients already on levodopa, which is where the company will now seek a path to approval ².

Cerevance remains private. It was formed in late 2016 as a joint venture between Lightstone Ventures and Takeda, which supplied the research team, laboratories and first drug candidates, and it started with $36 million ¹. In 2022 it agreed a brain target discovery collaboration with Merck & Co ¹. Investigator Robert Hauser of the University of South Florida argued that off time "captures only one aspect of the disease" and that looking at the measures together "may give a fuller picture" of a treatment's benefit ¹.

Caveats

The data so far come from company statements reported by the trade press rather than a peer-reviewed publication ¹². The off-time benefit was 0.61 hours a day at the higher dose, and the on-time gain only narrowly reached significance ¹. The trial ran for 12 weeks, so it says nothing yet about longer-term benefit or safety. The regulatory route is not settled: Fierce Biotech reports that Cerevance plans to seek FDA approval, while chief executive Craig Thompson said the company will discuss the results with the FDA to "determine next steps" ².