Health Canada is warning healthcare professionals of potential complications for patients treated with Alexion's Soliris (eculizumab) that are vaccinated GSK's meningitis B vaccine Bexsero.
Specifically, Health Canada says it found that patients treated with Soliris have an increased risk for two blood conditions, hemolysis and low hemoglobin, after being vaccinated with Bexsero.
"During a safety review of Bexsero … Health Canada found more reports of serious adverse reactions with Bexsero in patients with complement mediated diseases (such as paroxysmal nocturnal hemoglobinuria [PHN] and atypical haemolytic uremic syndrome [atypical HUS]) who were being treated with Soliris," the agency writes.
Complications With Bexsero
Because patients treated with Soliris are more susceptible to serious infections, including meningitis, Health Canada has recommended that all patients get vaccinated for meningitis before starting on Soliris.
However, when Soliris was approved in 2009 there were no available vaccines for meningitis B.
Now, Health Canada says that patients taking Soliris should only be vaccinated with Bexsero "only after their disease has been controlled and within one week following Soliris infusion, when the Soliris concentration in the blood is considered to be relatively high."
However, for patients who have not yet begun taking Soliris, Health Canada recommends to get vaccinated for meningitis A, C, Y W135 and B before, or on the same day as initiating treatment with Soliris.
Soliris is the first drug approved to treat both PHN and atypical HUS, two rare and life-threatening acquired immune conditions.
However, Soliris is also one of the most expensive drugs in the world, and has drawn controversy in Canada and elsewhere over its price. According to Canada's Patent Medicine Prices Review Board (PMPRB), Soliris cost as much as CAD $500,000 or $700,000, depending on which condition it's used to treat.
In 2015, the PMPRB sought an order against to get the company to reduce its price and require Alexion to keep the price of the drug and pay back "excess revenues" it earned since 2012. In July 2016, the order was finalized after Alexion failed in its bid to block the order through a constitutional challenge against the PMPRB.