On October 15th, the Food and Drug Administration approved its second interchangeable biosimilar drug.  That drug is Cyltezo (adalimumab-adbm), produced by Boehringer Ingelheim, which obtained biosimilar approval on August 25, 2017.  In this recent approval, the FDA determined that Cyltezo is interchangeable with AbbVie's Humira (adalimumab), its reference product.  Cyltezo is the first monoclonal antibody biosimilar to be deemed an interchangeable biosimilar drug product.

One of the benefits of interchangeability is that physicians' input (and approval) is not needed for substitution, which can be implemented at the pharmacy level.  The approval was based on the provisions of the Biological Price Competition and Innovation Act of 2009 (BPCIA), enacted with the Affordable Care Act (commonly known as "Obamacare") codified at 42 U.S.C. § 262 et seq.  Subsection (k) relates to the standards for biosimilarity; the FDA (and the statute itself) distinguish between biosimilarity and interchangeability inter alia by applying a heightened standard for interchangeability.  Specifically, the statute requires that an interchangeable product is biosimilar and can be expected to produce the same clinical result as the reference product in any given patient; and that for a biological product that is administered more than once to an individual, the risk in terms of safety or diminished efficacy of alternating or switching between use of the biological product and the reference product is not greater than the risk of using the reference product without such alternation or switch.  42 U.S.C. §§ 262(I)(3) and 262(k)(4).

The FDA approved Cyltezo for several uses in adult patients: these include moderately to severely active rheumatoid arthritis, active psoriatic arthritis, active ankylosing spondylitis, moderately to severely active Crohn's disease, moderately to severely active ulcerative colitis, and moderate to severe chronic plaque psoriasis.  In juvenile patients (two years of age and older), Cyltezo was approved for moderately to severely active polyarticular juvenile idiopathic arthritis and for Crohn's disease in patients six years of age and older.

Cyltezo was approved as a single-dose, pre-filled glass syringe at two amounts (40 mg/0.8 mL, 20 mg/0.4 mL), to be administered subcutaneously by a physician or other medical staff acting under physician supervision.  The approval notes some side effects, the most common of which are upper respiratory and sinus infections, injection site reactions, headache, and rash, although more serious albeit more rare side effects include malignancies.  The severity of these possible side effects provoked the FDA to include a so-called boxed warning to health care professionals regarding infections and lymphoma.

FDA Commissioner Janet Woodcock issued a statement on the occasion of Cyltezo's approval, saying that:

The biosimilar and interchangeable approval pathway was created to help increase access to treatment options for patients with serious medical conditions.  We continue to be steadfast in our commitment to provide patients with alternative high-quality, affordable medications that are proven to be safe and effective.

This approval is the thirty-first approval and thirtieth biosimilar product approved under the BPCIA.