WESTMINSTER, Colo. (AP) — Allos Therapeutics Inc. said Friday that regulators approved its injectable drug Folotyn as a treatment for peripheral T-cell lymphoma, a group of rare, agressive blood cancers, sending its shares soaring. Allos said the Food and Drug Administration granted accelerated approval, allowing the company to market Folotyn for use in patients whose cancer has returned or not responded to previous treatment. Allos expects to begin selling the drug in October. There are no drugs on the market that treat peripheral T-cell lymphoma, Allos said. The company said the FDA ruling was based on evidence that patients treated with Folotyn in clinical trials had their tumors shrink. It has not been proved that the drug, also known as pralatrexate, can stop the spread of the disease or prolong survival, Allos said. The company said the most-common side effects noted in the clinical trial included inflammation of mucous membranes, nausea, fatigue, and lowered levels of blood platelets. Allos said about 5,600 cases of peripheral T-cell lymphoma were diagnosed in the U.S. in 2008, and between 25 and 40 percent of patients survive for five years after their diagnosis. In premarket trading, Allos shares climbed $1.35, or 16.6 percent, to $9.50.