GSK's lung cancer treatment secures "orphan drug" status in Japan

(Alliance News) - GSK PLC on Monday said Japanese health authorities had granted "orphan drug" status to its lung cancer treatment.

The London-based pharmaceutical firm's medication risvutatug rezetecan, which it has dubbed ris-rez, is a B7-H3-targeted antibody-drug conjugate.

According to GSK, phase-one clinical trials have linked ris-rez to "durable responses" in certain small-cell lung cancer patients. Phase-three testing of the medication began in August.

GSK noted that SCLC "is associated with high rates of relapse, few treatment options and poor prognosis".

"Lung cancer is the second most common cancer in Japan, and SCLC makes up 10-15% of cases. Of patients with SCLC, 70% have [extensive-stage] SCLC, meaning the cancer has spread throughout one or both lungs and/or to other parts of the body," the drug company explained.

"Most patients with ES-SCLC relapse after initial treatment and the median overall survival with standard-of-care for these patients is approximately 8 months."

Orphan drug designation is a means of accelerating a drug's approval process in Japan.

"This is the sixth regulatory designation for ris-rez, which is being developed in a range of solid tumours, including lung, prostate and colorectal cancers," GSK said.

The company obtained worldwide commercialisation rights for ris-rez from Hansoh Pharmaceutical Group Co Ltd, excluding mainland China, Hong Kong, Macau and Taiwan.

Riz-res already has orphan drug designation from the US Food & Drug Administration for SCLC and the European Medicines Agency for cancer variants which include SCLC. It has "priority medicines" designation from the EMA for extensive stage-SCLC and "breakthrough therapy" status from the FDA for osteosarcoma and extensive stage-SCLC.

GSK shares fell 1.3% to 1,925.00 pence on Monday morning in London.

By Holly Munks, Alliance News reporter

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