Merck & Co has agreed a deal to buy California biopharma company Afferent Pharma, adding a drug candidate for chronic cough to its pipeline.
The deal – which includes $500m upfront in cash and up to $750m if development and commercial objectives are met – gives Merck access to Afferent’s pipeline of drugs that target P2X3 purinergic receptors found on nerve cells.
These receptors seem to become more common after nerve injury or inflammation, and drugs that block them are thought to have potential in a broad range of ‘neurogenic’ indications in which nerves become hyper-sensitised.
For Merck, the deal centres around Afferent’s lead P2X3 receptor antagonist AF-219, an orally-active drug that is currently being tested in a phase IIb trial in patients with chronic or ‘pathologic’ cough that can last for months or even years.
Afferent estimates that persistent cough affects up to 10% of the US population, and around 17% of these people derive no benefit from current treatments such as opioid drugs and corticosteroids.
In a statement Merck’s R&F head Roger Perlmutter said chronic cough represents “an area of significant unmet medical need”.
Clinical data presented at the American Thoracic Society (ATS) in May showed that AF-219 significantly reduced cough frequency at a dose of 50mg twice-daily. A second phase involving lower doses will generate results later this year and Afferent has said it hopes to start a phase III programme in chronic cough next year.
In addition to chronic cough, AF-129 is also in a phase II trial for cough and breathlessness associated with the respiratory disease idiopathic pulmonary fibrosis (IPF). Meanwhile a second pipeline candidate – AF-130 – is in phase I trials for resistant high blood pressure and preclinical development for migraine.
Merck has been working on its own early-stage R&D programme in the P2X3 area, along with other big pharma companies including AstraZeneca and Shionogi. Afferent licensed its programme from Roche in 2009.
The deal ties in with a pledge by Merck chief executive Ken Frazier earlier this year that the company would step up its efforts to bolster its pipeline through licensing and acquisition deals.