The U.S. Patent and Trademark Office rejected Alvogen Pine Brook LLC's request for a review of the patents on Celgene Corp.'s blood cancer drug Revlimid, Reuters reported.

Pine Brook, N.J.-based Alvogen's filing challenging the validity of Revlimid's patents was turned down by the Patent Trial and Appeal Board, a court overseen by the patent office.

The court's rejection follows Alvogen Inc.'s launch of generic of Revlimid in the EU on Feb. 12.

Revlimid accounted for more than 60% of the Summit, N.J.-based Celgene's overall sales in 2018, about $9.69 billion, an 18% increase from 2017. The drug is approved in the U.S. for patients with multiple myeloma and myelodysplastic syndrome who need transfusions to replace blood cells and for those with mantle cell lymphoma that has progressed or relapsed after two treatments.

The therapy is being reviewed by the U.S. Food and Drug Administration in combination with Roche Holding AG's Rituxan for treating patients with follicular and marginal zone lymphoma whose disease returned or did not respond to initial treatment.

Bristol-Myers Squibb Co. in January started a $74 billion takeover of Celgene, with executives saying Revlimid made the deal more compelling. The drug is facing imminent generic competition, but Bristol-Myers executives dismissed concerns about sales erosion, telling investors that Revlimid will continue to be a valuable asset for the combined company.