Spectrum Pharmaceuticals (SPPI), an Irvine, Calif.-based biotech focused on hematology and oncology, has completed its acquisition of Allos Therapeutics, a Westminster, Colo.-based developer of small molecule drugs.

The acquisition was through a “short-form” merger of Sapphire Acquisition Sub, a wholly-owned subsidiary of Spectrum, with and into Allos, with Allos surviving the merger and continuing as a wholly-owned subsidiary of Spectrum.

Immediately prior to the merger, Spectrum successfully completed its cash tender offer to purchase all of the outstanding shares of common stock of Allos. Based on information provided by the depository for the tender offer, a total of 96,259,850 shares were validly tendered and not withdrawn at the expiration of the tender offer (including 2,368,421 shares tendered pursuant to the guaranteed delivery procedures set forth in the Offer to Purchase), representing approximately 89.98% of the outstanding shares of Allos common stock (or approximately 87.77% of such outstanding shares if none of the shares tendered pursuant to the guaranteed delivery procedures are actually delivered).

Pursuant to the terms of the tender offer, Spectrum has accepted for payment all shares validly tendered and not validly withdrawn during the offering period, and has paid an amount equal to the aggregate consideration for all such shares to the depositary for the tender offer, to be disbursed to the Allos stockholders in accordance with the terms of the tender offer.

“The completion of the Allos acquisition is a major milestone for Spectrum, meaningfully diversifying our revenues and bringing together programs and products that we believe will have significant synergies, both in the very near term and over ensuing years,” said Rajesh C. Shrotriya, MD, chairman, CEO and president of Spectrum Pharmaceuticals. “We have had several months to prepare for this and our integration plan is designed to be effective and swift. We will provide further updates on the acquisition and integration at upcoming investor conferences.”