NEW YORK (AP) — GlaxoSmithKline PLC and its development partner Genmab came one step closer Friday to gaining approval on their cancer treatment Arzerra after an advisory panel recommended the FDA approve the therapy. The panel recommended that the FDA approve the drug in a 10 to 3 vote. Arzerra is aimed at treating chronic lymphocytic leukemia (CLL), a type of blood cancer and one of the most common forms of adult leukemia. Specifically, the company is asking the FDA to approve the drug as a treatment for patients who have either failed other treatments or who otherwise can’t use standard therapies. “The committee’s positive vote in support of ofatumumab (Arzerra) is a potential milestone for patients with CLL,” said Dr. Debasish Roychowdhury, head of medicines development within Glaxo’s oncology unit. “While current initial treatments for CLL can provide prolonged remissions, some patients will progress rapidly and relapse, which highlights the need for new therapies.” The panel’s recommendation, which the FDA normally follows though it is not required to, came after a somewhat critical staff report from the agency on Wednesday. That report questioned some of the study data being used by the companies to gain accelerated approval. The study itself did not compare Arzerra with other treatments. Also, it looked at patients who had been previously treated with the chemotherapy Fludara and with both Fludara and Campath, which is made by Genzyme Corp. The staff report recommended an additional study on the drug to focus on a patients who had only received prior treatment with Fludara. The report said that portion of the data did not meet the FDA’s regulatory standard. Meanwhile, the report said it will focus on data from patients who had previously taken both Fludara and Campath. Other concerns focused on whether there were sufficient diagnostics, such as CT scans, following treatment to determine the actual effect of the drug on tumors. “FDA acknowledges that administration of ofatumumab (Arzerra) as a single agent yields antitumor activity in patients with CLL,” the staff report said. But the report also said “the existence of anti-tumor activity alone does not satisfy the standards for accelerated approval.” Denmark-based Genmab and U.K.-based GlaxoSmithKline have been partners on Arzerra since 2006 in a deal worth up to $2.1 billion for Genmab. Arzerra has been viewed as a potential blockbuster drug. “Today’s (panel) vote is positive affirmation for this medicine, which is a result of years of dedicated research and collaboration between Genmab and Glaxo,” said Lisa N. Drakeman, chief executive of Genmab. Elsewhere, biotechnology giant Genentech and partner Biogen Idec Inc. are preparing for a review of Rituxan as a treatment for CLL, in combination with chemotherapy. The drug is already approved as a rheumatoid arthritis and non-hodgkins lymphoma treatment. Genentech is now part of Switzerland-based Roche.