Data From a Phase I Study of a Drug to Treat Systemic Mastocytosis Has Been Released

Promising data from the ongoing Phase I clinical trial Explorer has been announced by Blueprint Medicines Corporation. The trial is designed to evaluate the effects of the experimental drug avapritinib in the treatment of patients with systemic mastocytosis. The full article, which contains a more detailed report of the data, can be found here at PR Newswire.

Systemic mastocytosis (SM) is a form of mastocytosis that mainly affects adults. It is caused by an accumulation of mast cells in body tissues including the skin, bones, and organs. Mast cells are produced in the bone marrow and are involved in the immune system. People who are affected by SM may experience headaches, stomach pain, hives, and anaemia, amongst other symptoms. SM is also divided into four forms, each of which is associated with different typical effects. The four forms are indolent SM, SM with an associated hematologic non-mast cell lineage disorder, aggressive SM, and mast cell leukaemia. In the majority of cases of SM, the condition is caused by alterations to the KIT gene. The experimental treatment, avapritinib, functions by selectively inhibiting KIT and PDGFRA.

The current results of the ongoing Phase I trial of avapritinib are encouraging. The overall response rate is 83%, and the response was found to be durable for up to 22 months. At the data cutoff date of 30th April 2018, 79% of responders continued on the treatment. All patients who were evaluated showed decreases in at least one measure of mast cell burden. The trial involved patients with several forms of SM.
Based on these results, Blueprint Medicines is planning to further study the drug in two Phase 2 clinical trials on patients with SM. One of these planned studies is called Pathfinder and is an open-label, single-arm trial for patients with advanced SM. The other is called Pioneer and an expansion of the company’s development program. It is a randomized, placebo-controlled trial for patients with indolent and smouldering SM. Both are expected to be initiated by the end of 2018.

Anna Hewitt

Anna Hewitt

Anna is from England and recently finished her undergraduate degree. She has an interest in medicine and enjoys writing. In her spare time she likes to cook, hike, and hang out with cats.

Share this post

Share on facebook
Share on google
Share on twitter
Share on linkedin
Share on pinterest
Share on print
Share on email