A symposium called the New Treatment Paradigm for Small Cell Lung Cancer (SCLC) organized by the Hong Kong Cancer Therapy Society (HKCTS) with support from Luye Pharma Group (Luye Pharma) took place in Hong Kong yesterday. At the conference, Luye Pharma announced the launch of its innovative drug Zepzelca^® (lurbinectedin) for the treatment of SCLC in both Hong Kong and Macao, the two Special Administrative Regions of China.

Lurbinectedin is a new chemical entity with a novel mechanism of action. It was approved for launch in Macao in November 2023 and in Hong Kong in December 2023 for the treatment of adult patients with metastatic SCLC with disease progression on or after platinum-based chemotherapy. The drug was also approved by the U.S. Food and Drug Administration (FDA) through the accelerated approval process in 2020. For 27 years, it has been the only new chemical entity approved by the U.S. FDA for the treatment of relapsed SCLC since 1997.

Lurbinectedin has overcome a bottleneck in the second-line treatments of SCLC 

SCLC is one of the most aggressive lung cancers, with a five-year survival rate of only 7%^[1]. Most patients would experience a relapse or develop drug resistance after the initial treatment, with an mOS (median Overall Survival) of only 4 to 5 months after receiving further chemotherapy^[2].

"SCLC is one of the most malignant and highly recurrent subtypes of lung cancer, and for over 20 years, there has been no substantial progress in developing second-line treatments for the disease after a relapse and in improving patient survival," said Dr. Herbert Loong, an Associate Professor from the Department of Clinical Oncology at the Chinese University of Hong Kong and a council member of HKCTS, who chaired the symposium. "Different from traditional chemotherapy, lurbinectedin is a selective inhibitor of oncogenic transcription with notable activity in SCLC. We believe it can become a new standard second-line treatment for SCLC and help improve patient survival."

Promising results for Chinese patients in a clinical study

The approval of lurbinectedin in countries and regions including the U.S., Hong Kong and Macao is mainly based on an open-label, multicenter and single-arm study (a Phase 2 basket trial) in 105 adult patients with SCLC (including both platinum-sensitive and platinum-resistant patients) who experienced disease progression after receiving platinum-based chemotherapy. In this trial, they were treated with lurbinectedin alone by receiving 1-hour intravenous infusion of the drug every 3 weeks at a dose of 3.2mg/m². The study was published in The Lancet Oncology^[3]. It demonstrated an ORR (Overall Response Rate) of 35.2%, an mDoR (median Duration of Response) of 5.3 months, and an mOS of 9.3 months for all patients treated with lurbinectedin^[3].

"Lurbinectedin was found to be superior to current standard treatments based on their historical data in terms of anticancer activity and safety, and it was effective in both platinum-sensitive and platinum-resistant SCLC patients," said Dr. Antonio Calles, a specialist from the Department of Medical Oncology at Hospital General Universitario Gregorio Marañón in Madrid, Spain. "In addition to being used as a monotherapy, lurbinectedin is also expected to be used in combination with chemotherapy, immunotherapy or other therapies, to allow SCLC patients to benefit more from it."

A single-arm, Phase 1 clinical study with dose escalation and expansion for lurbinectedin was conducted, to evaluate its safety, tolerability, pharmacokinetics (PK) and preliminary efficacy in Chinese patients with advanced solid tumors, including recurrent SCLC. The study showed an ORR of 45.5%, an mDoR of 4.2 months, and an mOS of 11.0 months for SCLC patients treated with lurbinectedin (at the FDA-approved dose of 3.2 mg/m² via 1-hour intravenous infusion every 3 weeks).

At the symposium, Professor Sheng Ye, Director of Clinical Oncology at the First Hospital of Sun Yat-sen University, said: "This study was designed to evaluate the preliminary efficacy and safety of lurbinectedin in Chinese patients. We are excited to see that the performance of lurbinectedin at the FDA-approved dose in Chinese patients with relapsed SCLC whose condition has progressed after receiving a first-line platinum-based chemotherapy is comparable to or even better than its performance in the SCLC cohort of an overseas Phase 2 basket trial in terms of efficacy and patient survival. Lurbinectedin is expected to become a new treatment option of value for Chinese SCLC patients."

Helping to make innovative drugs more accessible for patients

To date, lurbinectedin has been approved for launch in 16 countries and regions worldwide. Luye Pharma has been granted the rights to develop and commercialize lurbinectedin in Chinese mainland, Hong Kong, and Macao, to allow Chinese patients to benefit from the innovative therapy as soon as possible. In addition to being approved for launch in Hong Kong and Macao, the drug is also under review for its New Drug Application (NDA) in Chinese mainland with a priority review designation.

Andy Siow, APAC VP of Luye Pharma (International), said: "After more than two decades, there is finally a significant advancement in addressing the relapsed SCLC, offering patients the long-awaited hope and clinically improved outcomes. With the introduction of Zepzelca in Hong Kong and Macao, we are actively collaborating with various stakeholders to enhance its accessibility to all patients. Our objective is to expedite patient access to the medication, enhancing their survival prospects and alleviating treatment burdens."