GSK's Blenrep Combinations: A Strategic Oncology Play in Japan's Growing Multiple Myeloma Market

The race to dominate high-margin oncology markets is heating up, and GSK ($GSK) has positioned itself at the front of the pack with its breakthrough therapy Blenrep (belantamab mafodotin). Combining clinical prowess with strategic regulatory momentum, Blenrep’s data-driven profile in relapsed/refractory multiple myeloma (RRMM) makes it a compelling buy for investors seeking exposure to a rapidly growing therapeutic area. Let’s dissect the catalysts driving this opportunity.

The Clinical Breakthrough: DREAMM Trials Redefine Standards of Care

Multiple myeloma, a blood cancer with over 160,000 global cases annually, has long been a battleground for novel therapies. GSK’s phase III DREAMM-7 and DREAMM-8 trials now stand as landmarks in this fight.

DREAMM-7 Trial:
In head-to-head testing, Blenrep combined with bortezomib/dexamethasone (BVd) delivered a median progression-free survival (PFS) of 36.6 months—more than doubling the 13.4-month PFS of the comparator daratumumab regimen. The hazard ratio (HR) of 0.41 (p<0.001) underscored a 59% reduction in progression risk, with 69% of patients progression-free at 18 months versus 43%.

DREAMM-8 Trial:
For patients with prior lenalidomide exposure—a notoriously hard-to-treat population—Blenrep’s pomalidomide/dexamethasone (BPd) combination reduced progression/death risk by 48% (HR=0.52), with a 12-month PFS rate of 71% versus 51% for bortezomib-based therapy. Deep responses were transformative: 40% achieved complete remission versus 16%, signaling durable clinical impact.

These results are not incremental—they’re paradigm shifts. Blenrep’s BCMA-targeting ADC mechanism directly attacks cancer cells while minimizing damage to healthy tissue, offering a critical alternative to existing therapies like CD38 antibodies or proteasome inhibitors.

Regulatory Momentum: Japan’s Priority Review and Global Rollout

GSK’s regulatory strategy is as calculated as its science. In Japan—a market with 7,200 annual RRMM cases and a high willingness to pay for breakthroughs—Blenrep received orphan drug designation and priority review in 2024, accelerating its path to approval. This designation, finalized in May 2025, ensures pricing power in a market where oncology therapies command premium pricing.

Globally, the EU’s EMA accepted Blenrep’s combination application in July 2024, with a UK approval secured in April 2025. The U.S. FDA’s PDUFA date of July 2025 looms as a key catalyst, with Breakthrough Therapy status already secured.

Commercial Upside: A High-Margin Niche with Sustained Growth

The numbers here are staggering. Multiple myeloma therapies command annual prices exceeding $100,000 per patient, and Blenrep’s combination regimens target a population with limited alternatives. In Japan alone, even a modest 10% market share would translate to hundreds of millions in annual revenue.

Crucially, Blenrep’s mechanism offers synergy potential with GSK’s existing oncology portfolio and partnerships. The ADC’s BCMA targeting aligns with a growing class of therapies (e.g., CAR-T cells), creating cross-selling opportunities in combination regimens.

Why Buy Now?

• Near-Term Catalysts: U.S. approval in Q3 2025 and EU decisions in 2025-2026 will drive valuation inflection points.
• Pricing Power: Orphan status in Japan and the U.S. ensures premium pricing with minimal price erosion.
• Pipeline Leadership: Blenrep is the only approved BCMA ADC in RRMM, locking in first-mover advantages.

Risks? Minimal, But Manageable

Safety concerns around ocular side effects (managed via dose adjustments) and the need for supportive care have not derailed approvals. Competitors like Bristol-Myers Squibb’s BMS-986178 lag behind in clinical data, while CAR-T therapies face logistical hurdles.

Final Analysis: A Buy with Multi-Year Upside

The math is clear: Blenrep’s data, regulatory tailwinds, and addressable markets create a $1B+ annual revenue opportunity by 2030. With a current stock price undervaluing its oncology pipeline and multiple myeloma’s growth trajectory, this is a rare chance to invest in a therapeutic leader before its full potential is priced in.

Investors should act now—before the FDA’s July decision sparks a rerating. GSK’s Blenrep is not just a drug; it’s a strategic oncology asset primed to dominate a $10B+ market. The time to buy is now.