Agios Drops Tebapivat SCD: No Edge Over Existing Drugs

Agios Pharmaceuticals (AGIO) will discontinue development of tebapivat in sickle cell disease after Phase 2 results showed hemoglobin response rates consistent with the drug class but no differentiation to justify continued development. The stock dropped roughly 7% on the news, closing at $36.28 on July 23.

The numbers

• Ticker: AGIO
• Stock price: $36.28 (close July 23, 2026)
• Market cap: $2.16 billion
• Drug: Tebapivat, an oral pyruvate kinase RP activator
• Indication: Sickle cell disease (discontinued)
• Trial phase: Phase 2 (stopped)

Agios’s chief medical officer Sarah Gheuens said the results “did not establish the level of differentiation we believe is necessary to support continued development.” Hemoglobin response rates were consistent with the class of pyruvate kinase activators, meaning the drug worked but didn’t work better than what already exists.

Why differentiation matters in sickle cell

Sickle cell disease is a blood disorder where red blood cells become rigid and sickle-shaped, causing painful vaso-occlusive crises and chronic anemia. The treatment field has become crowded. The FDA approved two gene therapies in late 2023: Casgevy (Vertex/CRISPR) and Lyfgenia (Bluebird). Novartis sells Adakveo (crizanlizumab) for crisis prevention. Pfizer’s Oxbryta (voxelotor) was withdrawn from the market in 2024 over safety concerns.

Pyruvate kinase activators work by boosting ATP production in red blood cells, improving their energy metabolism and reducing sickling. The mechanism improves hemoglobin but does not directly address the vaso-occlusive crisis pathway that drives the disease’s most severe complications. In a post-gene-therapy world, incremental hemoglobin improvements are not enough to compete.

What remains for Agios

Agios still has mitapivat, approved as Pyrukynd for pyruvate kinase deficiency, in the RISE UP Phase 3 trial for sickle cell disease. The Phase 2 portion of RISE UP met its primary endpoint of hemoglobin response, and the Phase 3 is ongoing with data expected in 2027. This is now Agios’s only SCD catalyst.

HC Wainwright maintained its Buy rating on Agios but lowered its price target from $54 to $52, implying 43% upside from the current price. The firm’s confidence rests on the Pyrukynd franchise in thalassemia and pyruvate kinase deficiency, not SCD.

What to watch

The RISE UP Phase 3 readout is the binary event for Agios in sickle cell. If mitapivat shows differentiated efficacy in Phase 3, the SCD franchise survives. If it replicates tebapivat’s undifferentiated profile, Agios exits sickle cell entirely. The risk: RISE UP’s Phase 2 data showed mixed results, with responses in some patient subgroups but not others. Watch for any Phase 3 enrollment updates or interim signals.

Agios’s core value sits in Pyrukynd’s approved indications and its pipeline in thalassemia. The SCD setback narrows the investment thesis but does not break it. The $52 analyst target still implies meaningful upside.

Sources: Agios press release, Reuters coverage, HCPlive analysis, Finnhub coverage. See also our guide on how to read a clinical trial press release.