It has been over two years since I wrote Acceleron Pharma (XLRN) Has Two Potential Blockbusters, so an update is in order. Back then, on July 22, 2015, Acceleron closed at $32.18. It has been very volatile in the meantime, hitting $50.49 on December 29, 2015, but also $21.99 on October 13, 2015. That is part of the thrill (or opportunity, or danger) of investing in clinical-state biotechnology companies. On October 11, 2017, it closed at $38.76. In 2017 the trend has been upward, but very volatile:
Acceleron specializes in therapies affecting the TGF-Beta growth factor proteins. These are key regulators of human growth and tissue repair. Its three leading candidates are luspatercept, sotatercept, and ACE-083.
In my last article I mentioned dalantercept as a major pipeline candidate, but it failed to meet expectations.
Luspatercept for anemias is in Phase 3 trials for two indications. Structurally it is a large protein made by fusing modified activin receptor type IIb with the IgG1 Fc domain. This allows it to stimulate red blood cell formation by inhibiting members of the TGF-Beta family.
In short, luspatercept can prevent anemia in a different way than erythropoietin derivatives, which include Epogen and Aranesp. In Q2 Amgen (AMGN) sales of Epogen were $292 million, but a biosimilar, Pfizerâ€™s (PFE) Retacrit, may gain FDA approval soon. Epogen and similar drugs are sometimes called erythropoiesis-simulating agents, or ESAs.
Celgene (CELG) is partnering with Acceleron to develop Luspatercept. There are many causes of anemia. Epogen, for instance, is mainly used to treat chronic renal failure and anemia from chemotherapy.
For MDS (myelodysplastic syndromes, a blood cancer) Acceleron is conducting the MEDALIST trial. Patients in the trial have lower-risk, ring sideroblast-postive MDS.
For transfusion-dependent beta-thalassemia patients there is the Phase 3 BELIEVE trial. A phase 2 trial for non-transfusion independent agents…