The licenses Roche received under the collaboration will be returned to Atea, which will conduct clinical development and market AT-527


Roche Diagnostics administration and R&D buildings. (Credit: F. Hoffmann-La Roche Ltd.)

Roche has terminated its collaboration with Atea Pharmaceuticals to jointly develop a Covid-19 antiviral candidate AT-527 after the drug failed to show activity in a small study.

In October last year, Roche and Atea teamed up to co-develop manufacture and distribute AT-527, where Atea will receive an upfront payment of $350m.

However, the drug failed to reduce viral load in patients with mild or moderate Covid-19 in a mid-stage study, reported Reuters.

Upon termination of the collaboration, the licenses granted to Roche will be returned to Atea, which will have full rights to conduct clinical development and market AT-527 in the future.

AT-527 is an investigational, oral, purine nucleotide prodrug, with potential antiviral activity against several enveloped single-stranded RNA viruses.

Atea designed the drug to uniquely inhibit viral RNA dependent RNA polymerase, an enzyme that is said to play a key role in the replication of RNA viruses.

It works by a mechanism of action, with dual targets including chain termination (RdRp) and NiRAN inhibition, to create a high barrier to resistance.

Atea has completed a non-clinical programme, which showed that AT-527 was non-mutagenic, had no effects on fertility or reproduction and was non-teratogenic.

The company is evaluating the drug across multiple clinical trials in parallel, including the global Phase 3 MORNINGSKY trial.

Atea Pharmaceuticals founder and CEO Jean-Pierre Sommadossi said: “We believe strongly in the potential of AT-527 with its unique dual mechanism of action, antiviral activity against the major variants of concern and its market potential given the need for additional therapeutic options for Covid-19.

“We have the financial resources and the talent to independently drive forward the Phase 3 MORNINGSKY clinical trial program, and we continue to expect data from this trial during the second half of 2022.

“We are energised by the opportunity to move forward with full ownership, providing us with autonomy to efficiently bring AT-527 to market.”

Atea is a biopharmaceutical company focused on discovering, developing and marketing oral therapies that address unmet medical needs of patients with viral diseases.