As reported in Guru Focus, biotech company Protagonist Therapeutics has announced progression in their Phase 2 study on PTG-300 as treatment for patients with polycythemia vera, a rare cancer. Dr. Samuel Saks said, “While further follow up and data from additional patients will be needed to confirm the continuity of the robust clinical responses observed to date, we believe that this study provides a compelling rationale to initiate planning for a pivotal program in polycythemia vera.”
Polycythemia vera
Polycythemia vera (PCV) is a rare blood cancer that develops slowly over time. The condition causes a patient’s bone marrow to have an excess of red blood cells, white blood cells, and platelets, making the blood too thick. This thick blood can clot or lead to heart attacks, strokes, or bleeding. While some patients may have the condition without symptoms, others experience headaches, weakness, dizziness, itching (particularly after touching warm water), painful joints, sweating, double vision, abdominal pain, shortness of breath, and abnormal blood cell counts. The condition is thought to be genetic, caused by a defective JAK2 gene. Currently patients are often treated with phlebotomy, which involves drawing blood from patients to lower the blood volume and prevent clots; other treatments include aspirin, antihistamines, and medications to lower blood cell counts.
Phase 2 Results
The Phase 2 trial gave six patients the protocol dosage, which were individualized amounts of PTG-300 between 10 and 80mg for up to seven months. The administration of it was well tolerated by patients, and none have voluntarily discontinued receiving it. Dr. Saks explained that the treatment is thought to lessen the red blood cells in polycythemia by reducing iron that produces red blood cells. Because it went as planned, it took away the patients’ need for phlebotomy, the current treatment option. The success is encouraging, leaving the trial open for enrollment.
“In the near term, we are expanding the current study to include additional patients as the Company focuses on these encouraging results. We will also be hosting a scientific planning meeting with leaders in the field of myeloproliferative neoplasms and working with patient advocates to discuss pivotal and future studies in polycythemia vera. Our goal with these studies is to work to address the broad populations of patients that may benefit from this new non-cytoreductive treatment.” – Dr. Saks
The current results suggest that with this therapy, patients may be able to avoid using phlebotomy, which introduces other harmful side effects, like iron deficiency and high hematocrit levels, which increases the chance of strokes and heart attacks. Additionally, the new treatment can be self-administered each week, which could be a meaningful change for patients who could avoid doctor’s visits filling their schedule. The study is on track to continue to grow and is expected to include 50 patients in the next phase.
