Trimmed-down Acetylon proves more attractive to former opt-in partner Celgene

A new deal gives Celgene the bits of Acetylon it wants and cuts out those it doesn't.

After passing on an option to buy Acetylon in the summer, Celgene has come back with an offer for a slimmed-down version of the biotech.

Celgene's interest in the histone deacetylase (HDAC) inhibitor specialist goes back to 2013, when it fronted Acetylon a hefty $100 million and took an option to buy the company out for an estimated $1.7 billion. In August it decided not to pull that trigger but retained a minority equity stake in the firm.  

Fast forward four months and Celgene has had a change of heart—after Boston-based Acetylon announced it had spun out some of its programs into a separate company dubbed Regenacy Pharmaceuticals.

Terms have not been revealed, but it seems Celgene has spent the intervening months negotiating a new deal which gives it the bits of Acetylon it wants, and cuts out those it doesn't, most likely with a lower purchase price. 

Regenacy had been set up to develop HDAC6 inhibitor ricolinostat (ACY-1215)—for the treatment of non-cancer diseases including neuropathies—and preclinical selective HDAC1/2 inhibitor candidates for all human disease indications including sickle cell disease and beta-thalassemia.

That leaves Celgene with rights to ricolinostat in cancer—starting with Celgene's heartland multiple myeloma—and other applications such as neurodegeneration, and autoimmune disease. It also bags Acetylon's other HDAC6 inhibitors including citarinostat (ACY-241) which has just cleared phase 1 testing.

"Celgene is the optimal partner to realize the fullest potential of Acetylon's selective HDAC6 inhibitor programs in multiple myeloma and other oncology indications," said the biotech's chairman Marc Cohen.

"Their intimate knowledge of citarinostat and extensive experience in oncology make them uniquely qualified to continue development of these exciting programs." Celgene has an arsenal of myeloma therapies including top-selling Revlimid (lenalidomide) and follow-up Pomalyst (pomalidomide), and is already looking at the combination of citarinostat and Pomalyst in clinical trials.

Acetylon Chief Executive Walter Ogier will head up Regenacy when the deal goes through, and the new company will be owned by Acetylon's current shareholders, minus Celgene.

"We are excited to continue Acetylon's legacy through the receipt of rights to many of Acetylon's most promising compounds and the continued advancement of these clinical and preclinical programs in disease indications outside of Celgene’s areas of strategic focus," said Ogier.