New clinical data could result in the expansion of the approved uses for Amgen’s acute lymphoblastic leukaemia therapy Blincyto.
Blincyto (blinatumomab) is already licensed to treat patients with Philadelphia chromosome-negative (Ph-) relapsed or refractory B-cell precursor ALL, a rare and rapidly progressing cancer of the blood and bone marrow.
The drug became the first anti-CD19 drug to be approved by the FDA last December, and is also the lead product in Amgen’s bispecific T cell engager (BiTE) antibody programme, which direct cell-destroying T lymphocytes to attack malignant cells.
Now, top-line results from a phase IIb trial suggest the drug is also effective in the treatment of patients with this form of cancer that is Philadelphia chromosome-positive (Ph+), a group accounting for around a quarter of all adult ALL cases.
When treated with chemotherapy alone, patients with Ph+ ALL have a uniformly poor prognosis with very few survivors after five years after treatment, although haematopoietic stem cell transplants can cure 30% to 60% of cases.
Around 6,000 people in the US are diagnosed with ALL every year and roughly 25% die from the disease. The paediatric form of the diseases is more responsive to treatment but in adults the mortality rate is 20% to 40%.
Blincyto has been launched in the US with a price tag of $178,000 per two-cycle course, making it one of the most expensive drugs on the market, although given the rarity of ALL analysts have predicted peak sales in the region of $500m a year.
The company insists the price is justified by the massive unmet medical need in ALL patients and said in April that it was seeing “broad acceptance of the product with orders from most major institutions and good reimbursement access” in its first indication.