A broader range of indications in rheumatology combined with a Canadian push for biosimilar acceptance bodes well for Merck's Brenzys product.
Expanded indications have been approved for Merck’s Brenzys etanercept biosimilar by Health Canada. Originally approved in 2016 for the treatment of moderate-to-severe rheumatoid arthritis in adults and ankylosing spondylitis, Brenzys now has several additional approved indications: plaque psoriasis (PsO), psoriatic arthritis (PsA), and juvenile idiopathic arthritis (JIA).
Brenzys references Enbrel, which is already indicated by Health Canada for all the above-named indications. The drug is administered by subcutaneous injection.
In its statement about the expanded uses, Merck noted that roughly 1 million residents of Canada live with psoriasis and, of those, at least 10% will go on to develop PsA.
Etanercept is a tumor necrosis factor (TNF) blocker that reduces the amount of TNF-alpha made by the body’s immune system. Too much TNF-alpha is a characteristic of PsO, PsA, and JIA. This overproduction leads to painful, swollen joints and the development of thick, red, scaly patches known as psoriatic skin lesions, which can appear on any part of the body. Etanercept helps to ease these conditions.
JIA is the most common type of arthritis in children under the age of 16 and in Canada, roughly 10,000 youths have this condition.
“Merck is committed to providing Canadians with more therapeutic choices for patients and their treaters,” Anna Van Acker, president of Merck Canada, said in the statement.
Under the category of PsO, Canada Health has approved Brenzys for the treatment of adults with chronic moderate-to-severe PsO who are candidates for systemic therapy or phototherapy and also pediatric patients 4 to 17 years of age with chronic severe PsO who are candidates for systemic therapy or phototherapy.
In patients aged 4 to 17 years with an inadequate response to disease-modifying antirheumatic drugs, Brenzys is approved for the treatment of moderate-to-severe polyarticular JIA.
Full Steam on Biosimilars
Various Canadian provinces are moving aggressively toward implementation of biosimilars in an attempt to save money and improve access to health care. British Columbia is furthest ahead with these initiatives and recently reported total savings of $96.6 million, which it plowed back into health system investments that made other forms of care more available for patients.
In the most recent phase of this transition, British Columbia established mandatory switching to biosimilar rituximab for patients in its PharmaCare prescription coverage plan. Other Canadian provinces are following suit with similar switching programs, but the overall usage picture for biosimilars in Canada shows that the market for these drugs remains small.
Biosimilars have 8% of the Canadian market relative to originator products. In the United States, biosimilars command just 2.3% of the biologics marketplace, according to a recent Pfizer presentation.