ALX Oncology (ALXO) Q1 2026 Earnings Transcript

ALX Oncology reported encouraging Phase Ib/II data for evorpacept plus zanidatamab in heavily pretreated HER2-positive metastatic breast cancer: 33% ORR in all 24 patients, 60% in centrally confirmed HER2-positive patients, and 100% ORR in the 5-patient CD47-high/HER2-positive subset. Durability was notable, with 20.2 months median DOR and 22.1 months median PFS in CD47-high/HER2-positive patients versus 3.4 months in CD47-low patients. Management said ASPEN-09 remains on track for interim data on ~80 patients by mid-2027 and reiterated plans for a CD47 companion diagnostic, while ALX2004 Phase I safety data is expected in 2H26.

Analysis

The key market takeaway is not the headline response rate, but the emerging biomarker wedge: ALXO is transitioning from a broad HER2-combo story into a narrower, potentially much higher-value CD47-selected franchise. That matters because in late-line oncology, efficacy without selection is often just another transient read-through; biomarker enrichment can convert an interesting signal into a registrational path with materially lower sample-size requirements and a cleaner commercial narrative.

The second-order effect is competitive pressure on every post-T-DXd HER2 strategy. If these data hold, ALXO’s combination could sit above the crowded ‘next after ENHERTU’ pack and force competitors to justify why they can beat a biomarker-selected macrophage-priming mechanism on durability, not just ORR. The real economic lever is the companion diagnostic: if Ventana/ALXO can validate a reproducible cutoff, it expands pricing power by concentrating treatment in the highest-response subset and reduces payer pushback around an expensive combo in a refractory population.

The main risk is not biology alone; it is translation from a 5-patient high-signal subset to a larger, more heterogeneous Phase II/III dataset. The call itself hints at this: the optimal cutoff is still unresolved, central HER2 confirmation meaningfully changes apparent efficacy, and the company may need a conventional Phase III rather than accelerated approval. In other words, the stock can re-rate on continued de-risking over the next 12-18 months, but it can also give back a large portion of gains if the mid-2027 readout compresses toward the low-30s ORR / ~6-month PFS floor that management described as merely acceptable rather than transformative.

Key Decisions for Investors

• Go long ALXO on pullbacks over the next 1-3 weeks, but size it as a catalyst-driven biotech trade, not a core hold; thesis is a continued rerating into the mid-2027 ASPEN-09 data if enrollment stays on track and the CD47-selected signal remains intact.
• Use call spreads rather than stock if liquidity allows: buy ALXO Jan-2027 or Jan-2028 upside calls and finance with higher strikes; this captures the binary rerate potential while limiting downside if the larger readout blunts the biomarker effect.
• Pair ALXO long against a basket short of crowded post-T-DXd HER2 development names or broader small-cap biotech exposure; the edge is differentiation via selection, not sector beta.
• If holding ALXO into the mid-2026 ALX2004 safety update, trim into strength unless safety is clean and dose escalation continues upward; that program is a secondary catalyst but not yet a valuation anchor.
• Watch for any disclosure of CD47 prevalence or cutoff optimization in ASPEN-09 screening; if prevalence is meaningfully below management’s implied range, reduce exposure because the commercial TAM and Phase III design both compress.