CVS Health, operator of CVS Caremark, the second-largest pharmacy benefit manager in the U.S., recently announced that it plans to exclude 31 more prescription medications from insurance coverage in 2016, including the type 2 diabetes drug Invokana.
CVS, Express Scripts Dominate Market
According to a Wall Street Journal report, CVS and Express Scripts Holding Company together dominate the U.S. market for the administration of drug-benefit plans for employers and insurers. Excluding more drugs from coverage if there are viable alternatives is thought to be an attempt to force greater price discounts from manufacturers and steer patients to other drugs that are equally safe and effective but cost less. Drug makers typically give discounts in the form of rebates to pharmacy-benefit managers (PBMs) to ensure favorable coverage on preferred drug lists.
Other medications excluded from the CVS Caremark 2016 formulary were Invokana’s related combination treatment Invokamet; Viagra, the world’s first approved medication for erectile dysfunction, and the multiple sclerosis drugs Avonex and Plegridy. Viagra’s revival medication, Cialis, will remain on CVS Caremark’s approved drugs list.
What is Invokana?
The U.S. Food and Drug Administration (FDA) approved Invokana in March of 2013 as the first drug in a new class of oral agents to lower blood sugar in patients with Type 2 diabetes. Invokana is is marketed by Janssen Pharmaceuticals and works by inhibiting the normal function of the kidney, which is to return any glucose to the blood while excreting other unwanted elements. Instead, Invokana causes substantial amounts of sugar to be excreted in the urine, lower blood sugar levels.
Invokana drew criticism within its first year of release when five different adverse effects related directly or indirectly to renal toxicity were reported to the FDA, including:
- Kidney failure or impairment
- Dehydration or fluid imbalances
- Kidney stones
- Urinary tract infections
- Abnormal weight loss
The FDA Adverse Event Report System found at least 20 cases discovered between March 2013 and June 2014 where type-2 diabetes patients developed some form of ketoacidosis, a life-threatening condition that occurs when the body cannot use glucose as a fuel source because of a lack of insulin.