Spectrum Pharmaceuticals and Allos Therapeutics Announce Additional Extension of Tender Offer Period for Shares of Allos Therapeutics

Spectrum PharmaceuticalsShiv Kapoor, 702-835-6300Vice President, Strategic Planning & Investor RelationsorAllos TherapeuticsMonique Greer, 720-540-5268Vice President, Corporate Communications & Investor Relations

Spectrum Pharmaceuticals, Inc. (NasdaqGS: SPPI) (Spectrum) and Allos Therapeutics, Inc. (NasdaqGS: ALTH) (Allos) today announced that Spectrum has provided an additionalextension of the offer period in connection with its tender offer to purchase all of the outstanding shares of common stock of Allos for $1.82 per share in cash, without interest and less any applicable withholding taxes. The extension was made in order for Spectrum and Allos to continue cooperating with the Federal Trade Commission (FTC) in relation to the previously announced Request for Additional Information and Documentary Material that each party received on May 9, 2012 from the FTC under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended, applicable to the acquisition of Allos by Spectrum.

The offer, which was previously scheduled to expire at 5:00 p.m., Eastern time, on Monday, July 23, 2012, has been extended until 5:00 p.m., Eastern time, on Monday, August 6, 2012, unless extended for an additional period. All terms and conditions of the tender offer shall remain unchanged during the extended period.

The depositary for the tender offer has advised Spectrum that, as of 5:00 p.m., Eastern time, on July 20, 2012, a total of approximately 65,241,335 shares of Allos common stock, representing approximately 61.0% of the outstanding shares of Allos common stock, were validly tendered and not withdrawn.

Spectrum Pharmaceuticals, a biotechnology company with a primary focus in oncology and hematology, currently markets two oncology drugs, FUSILEV(levoleucovorin) for Injection and ZEVALIN (ibritumomab tiuxetan) Injection for intravenous use. In addition, Spectrum has two drugs, belinostat and apaziquone, in late stage development and a diversified pipeline of novel drug candidates in earlier stages of development. The Company's strategy is comprised of acquiring, developing and commercializing a broad and diverse pipeline of late-stage clinical and commercial drug products. The Company has aggressive business development and commercial operation teams that support a robust drug development program encompassing clinical development, medical research, regulatory affairs, biostatistics and data management. The Company also leverages the expertise of its worldwide partners to assist in the execution of its strategy. For more information, please visit the Company's website at .

Allos Therapeutics is a biopharmaceutical company committed to the development and commercialization of innovative anti-cancer therapeutics. Allos is currently focused on the development and commercialization of FOLOTYN (pralatrexate injection), a folate analog metabolic inhibitor. FOLOTYN is approved in the U.S. for the treatment of patients with relapsed or refractory peripheral T-cell lymphoma (PTCL). This indication is based on overall response rate. Clinical benefit such as improvement in progression free survival or overall survival has not been demonstrated. Allos is also developing FOLOTYN in other hematologic malignancies and solid tumors. Allos is headquartered in Westminster, Colorado. For more information, please visit Allos’ website at .