Mylan and Revance Therapeutics have unveiled plans to develop a biosimilar to Allergan's neuromodulator Botox.

The companies have announced a global collaboration and license agreement for the development and commercialisation of the proposed biosimilar, under which they will work together to gain its regulatory approval in the US, Europe and other markets.

The deal includes an upfront payment of $25 million to Revance, with contingent milestone payments upon achievement of certain clinical, regulatory and sales targets, plus sales royalties in all relevant markets.

“Global neuromodulator sales today are estimated at $4 billion and forecasted to grow steadily, exceeding $7 billion by 2024. Strategically, this partnership with Mylan allows Revance to remain focused on the development and launch of our own premium, long-acting RT002 neuromodulator, while also benefitting financially from potential future milestones and sales royalties on a short-acting biosimilar to Botox," said Dan Browne, Revance’s president and chief executive.

"This will be a significant opportunity for Mylan as we add another difficult-to-manufacture product to our pipeline,” added Mylan president Rajiv Malik.

Botox pulled in sales of more than $3 billion in last year, from its approved uses including chronic migraine, overactive bladder, severe underarm sweating, eyelid spasms and limb spasticity.