Pfizer has completed its acquisition of Silicon Valley biotech group Anacor securing access to its flagship non-steroidal topical PDE4 inhibitor crisaborole.

The US drugs giant announced earlier this year that it would purchase all of the outstanding shares of Anacor common stock for $99.25 per share, equating to a deal value of around $5.2 billion.

Crisaborole is currently being reviewed by US regulators as a potential treatment for mild-to-moderate atopic dermatitis (eczema), with a decision expected in by January 7 next year 2017.

According to Pfizer, the drug could achieve or exceed peak sales of more than $2 billion a year if it makes it to market, given its performance in Phase III trials and sizeable target market; up to 25 million people in the US are thought to suffer from the condition.

"Now that Anacor is part of Pfizer, we can accelerate our shared commitment to help patients with inflammatory disease, an area of high unmet medical need," said Albert Bourla, group president, Pfizer Innovative Health.

"We believe that Pfizer is in a position to quickly capitalise on the benefits offered by the combination with Anacor, including the potential for a near-term US product launch and subsequent commercialisation of crisaborole, a differentiated asset with compelling clinical data".

Anacor also holds the rights to Kerydin, a topical treatment for onychomycosis (toenail fungus) that is distributed and commercialised by Sandoz in the US.