3SBio Inc. a leading China-based biotechnology company focused on researching, developing, manufacturing and marketing biopharmaceutical products, announced that it has received official notification from China's State Food and Drug Administration (SFDA) granting 3SBio manufacturing approval for a TPIAO label extension for the treatment of Idiopathic Thrombocytopenic Purpura (ITP). The approval application was submitted in December 2008.

Jing Lou, MD, PhD, director and chief executive officer of 3SBio, commented: “We are pleased that TPIAO's label extension for the treatment of ITP has been approved by the SFDA. This additional indication complements our existing indication for chemotherapy induced platelet deficiency which has been rapidly adopted by the medical community since its approval in 2006.

3SBio was the first company globally to research, develop and commercialize a recombinant human thrombopoietin product and TPIAO remains the only product of its kind available in China. We will continue to focus on introducing innovative treatments for other unmet medical needs in China.”

Launched in 2006, TPIAO is a recombinant human thrombopoietin product initially approved in China for the treatment of chemotherapy induced thrombocytopenia, or platelet deficiency. The SFDA has now approved the extension of TPIAO's label to include the treatment of ITP.

ITP is characterized by an immune system malfunction that perceives the body's platelets as foreign and destroys them, potentially resulting in dangerously low platelet counts. There are an estimated eighty thousand patients diagnosed with ITP in China, with more than half of these patients resistant to conventional steroid treatment.

TPIAO represents a new approach for the treatment of ITP, by stimulating the TPO receptor, which is intended to have the effect of directly increasing platelet production to outpace platelet destruction by the immune system. The registration trial examined the safety and efficacy of a 14-day subcutaneous injection of TPIAO on ITP patients who are resistant to steroid treatment, followed by a 14-day observation period.

The results showed an overall patient response rate to TPIAO treatment of 60.27%, significantly higher than the Danazol control group response rate of 36.51%. Patients administered TPIAO also reached effective platelet counts in 7 days, compared to 10 days for patients within the control group.

The phase III study that 3SBio conducted was a multi-centre, randomized, placebo-controlled study in ITP patients who failed to respond to glucocorticoid treatment. All patients were administered Danazol, a synthetic steroid hormone drug routinely used to treat ITP.

The treatment group was administered an additional 1.0 microgram/kg TPIAO subcutaneously daily for 14 days. The primary endpoint of the trial was the measurement of effective platelet counts, in which maximum counts reached >50x109/L or increased >30x109/L over the baseline, during the 14-day treatment.

The results of the phase III study demonstrated TPIAO to be an effective treatment for ITP with tolerable mild adverse effects. The overall response rate in the treatment group and the control group was 60.27% and 36.51%, respectively (p=0.0104). The platelet response time, characterized by the time required for platelet counts to reach >50x109/L or increase >30x109/L over the baseline, for the first 25% of patients in the TPIAO treatment and control group was 7 and 10 days, respectively.

A 14-day TPIAO treatment was subsequently applied to patients in the control group whose platelet counts remained < 20x109/L. The overall response rate to the TPIAO treatment was 67%. The overall adverse events rate in the treatment and control group was 34.25% and 26.15%, respectively; the rate of TPIAO-related adverse events for the two groups, including mild sleepiness, mild dizziness, fatigue, mild allergic reaction, and paroxysmal visual field defect, was 15.07% and 4.08%, respectively.

3SBio is a leading, fully integrated, profitable biotechnology company focused on researching, developing, manufacturing and marketing biopharmaceutical products primarily in China. Its focus is on addressing large markets with significant unmet medical needs in nephrology, oncology, supportive cancer care, inflammation and infectious diseases.