Biosimilars have potential advantages in the treatment of cancer, as they introduce competition into the drug development process, which can lead to cost savings for patients and spur the development of new treatments.

What Are Biosimilars?

When chemical-based drugs are approved by the U.S. Food and Drug Administration (FDA), the company that developed the drug is given a patent—the exclusive right to produce and market the specific drug for a set number of years. After the patent expires and after FDA approval, other companies are allowed to produce and market drugs with the same chemical make-up; in all important ways, these drugs are the same as the original and are called “generics.”

Other medications—called “biologics”—are derived from a living system, such as a microorganism, plant or animal. Most biologics are very large and complex mixtures of molecules that are not easily identified or characterized, and are produced using cuttingedge technologies.

Biologics are also approved by the FDA and given a patent, and other companies are allowed to compete once that patent expires. However, those competing products have allowable differences because they are made from a living organism, and are called “biosimilars.” Although they are not an exact copy, biosimilars are expected to produce the same clinical result as the original product, and have no clinically meaningful differences in terms of safety, purity and potency.

Biologics include a wide range of products such as blood and blood components, vaccines, hormones and allergens (anti-allergy medications). Monoclonal antibodies are an especially important biologic; they are used in the treatment of many conditions, including breast cancer, lymphoma, rheumatoid arthritis, psoriasis, ulcerative colitis and Crohn’s disease.

The first biosimilar, filgrastim-sndz (Zarxio), was approved by the FDA in 2015. Both filgrastim-sndz and the original product, filgrastim (Neupogen) are bone marrow stimulants, which can help the body make white blood cells after cancer treatments.

The era of biosimilars has just begun, as the patents of many biologics are set to expire in the coming years.