Japan Reviews GSK's Blenrep Combo for Multiple Myeloma, Granting Priority as Orphan Drug

Global pharmaceutical company GSK has announced that Japan’s Ministry of Health, Labour, and Welfare (MHLW) has accepted a new drug application (NDA) for Blenrep (belantamab mafodotin), marking a significant step toward addressing the pressing medical needs of patients with relapsed or refractory multiple myeloma. The NDA submission seeks approval for Blenrep in combination with bortezomib plus dexamethasone (BorDex) or pomalidomide plus dexamethasone (PomDex). This breakthrough therapy has also received orphan drug designation, highlighting its potential in treating a disease where current options are increasingly limited.

The decision by Japan’s health ministry underscores the growing health concern posed by multiple myeloma in the country, with rising diagnoses over the past five decades. More than 7,200 new cases are reported in Japan each year, creating an urgent need for innovative treatments that offer hope to patients whose disease has become resistant to standard therapies.

Global Regulatory Momentum

This announcement marks the third major regulatory milestone for Blenrep combination therapies in 2024. The European Medicines Agency (EMA) accepted the drug for review in July, followed by the UK’s Medicines and Healthcare products Regulatory Agency (MHRA) earlier this month. Each regulatory submission has been bolstered by encouraging interim data from two critical phase III clinical trials: DREAMM-7 and DREAMM-8.

Hesham Abdullah, GSK’s Senior Vice President and Global Head of Oncology, emphasized the significance of these trials: "Blenrep combinations show potential to redefine the treatment of relapsed/refractory multiple myeloma. We are working closely with health authorities worldwide to bring these innovative treatments to patients as swiftly as possible."

Promising Trial Results

The DREAMM-7 and DREAMM-8 trials, which evaluated Blenrep in combination with BorDex and PomDex respectively, have yielded promising results. Both trials met their primary endpoints, demonstrating statistically significant improvements in progression-free survival (PFS) compared to standard of care. DREAMM-7 pitted Blenrep plus BorDex against daratumumab plus BorDex, while DREAMM-8 compared Blenrep plus PomDex to bortezomib plus PomDex. Though overall survival (OS) benefits have yet to reach statistical significance, ongoing follow-up suggests a positive trend.

Secondary endpoints across both trials have also shown deeper and more durable responses, suggesting Blenrep’s potential to outperform current treatment regimens. In terms of safety, the trials revealed that the combination therapies maintain tolerable safety profiles, consistent with the individual agents' known side effects.

Addressing Japan’s Growing Health Challenge

The need for new treatment options in Japan is particularly pressing given the rising number of multiple myeloma cases. As more patients become resistant to existing therapies, GSK’s Blenrep offers a promising new approach to managing relapsed or refractory disease.

A Closer Look at DREAMM-7 and DREAMM-8

DREAMM-7 included 494 participants from multiple centers, including Japan, who were randomized to receive either Blenrep plus BorDex or daratumumab plus BorDex. The trial’s primary endpoint was PFS, with key secondary measures like overall survival, duration of response (DOR), and minimal residual disease (MRD) negativity. Results from this trial were first unveiled at the American Society of Clinical Oncology (ASCO) Plenary Series in February 2024 and subsequently published in the New England Journal of Medicine.

DREAMM-8, featuring 302 participants, focused on more heavily pre-treated patients. All participants had been exposed to lenalidomide, a significant proportion were lenalidomide-refractory, and many had previous experience with daratumumab. Despite this challenging patient profile, Blenrep plus PomDex showed strong efficacy and tolerability, mirroring the results of DREAMM-7.

GSK’s latest success with Blenrep in Japan signals growing momentum for this innovative treatment as it continues to navigate global regulatory pathways. With significant unmet needs in multiple myeloma, particularly in countries like Japan, the acceptance of the NDA and orphan drug designation sets the stage for faster patient access to potentially life-saving therapies.

The expansion of the DREAMM trials to include Japanese patients ensures that the drug’s performance in local populations will be closely examined, with results expected to be presented at upcoming scientific forums.