Kleber Y. Fertrin, MD, PhD, assistant professor, University of Washington School of Medicine, and hematology oncologist, Seattle Cancer Care Alliance, discusses the potential of fostamatinib (Tavalisse) in the treatment of patients with chronic immune thrombocytopenia (ITP).

Fostamatinib is the first Syk inhibitor that was developed for the treatment of patients with chronic ITP. The agent was approved by the FDA in 2018 for use as a second-line therapy in patients with chronic ITP following an insufficient response to prior therapy. The approval was based on findings from 2 randomized trials and 1 open-label extension study. Notably, the agent has shown a response rate of approximately 30% in patients who are refractory to 2, or potentially 3, prior therapies.

However, many questions remain with the agent, explains Fertrin, such as whether or not the agent can be combined with other therapies. Additionally, although the agent has shown activity in a heavily pretreated population, it is unclear whether it will possess the same activity in earlier lines of treatment, says Fertrin. Many clinical trials with fostamatinib in heavily pretreated and treatment-naïve patients with chronic ITP are anticipated.

Videos

Dr. Fertrin on the Potential of Fostamatinib in Chronic ITP

Kleber Y. Fertrin, MD, PhD, assistant professor, University of Washington School of Medicine, Seattle Cancer Care Alliance, discusses the FDA approval of avatrombopag (Doptelet) in immune thrombocytopenia (ITP).

On July 1, 2019, the FDA approved a supplemental new drug application to expand the use of avatrombopag to include the treatment of adult patients with chronic ITP who have had an insufficient response to prior therapy. The approval of the oral thrombopoietin receptor agonist is largely based on findings from a phase III trial, which showed that avatrombopag led to a platelet count of >50,000 per µL after 8 days of therapy in the majority of patients with chronic ITP, and was also superior to placebo in sustaining platelet counts in the target range during a 6-month period.

The approval is a major breakthrough, says Fertrin, as it is the second therapy to be approved for patients with relapsed/refractory disease. Moreover, avatrombopag is well tolerated by patients in comparison to eltrombopag (Promacta), says Fertrin. As such, it may become the preferred therapy for patients with comorbidities. 

Kleber Y. Fertrin, MD, PhD, assistant professor, University of Washington School of Medicine, Seattle Cancer Care Alliance, discusses the FDA approval of avatrombopag in immune thrombocytopenia (ITP).

Kleber Y. Fertrin, MD, PhD

Articles

Dr. Fertrin on the Potential of Fostamatinib in Chronic ITP

Dr. Fertrin on the FDA Approval of Avatrombopag in ITP