Physicians in Europe and the United States will soon be able to choose between two SGLT-2 inhibitors for the treatment of type 2 diabetes. Following J&J's Invokana (canagliflozin), AstraZeneca's Farxiga (dapagliflozin) got approved by the FDA. That's not a typo, the brand name will be Forxiga in Europe and Farxiga in the United States. Decision Resources have consistently taken the stance that SGLT-2 inhibitors have very similar clinical profiles, so I compared the prescribing information, or package inserts for the two drugs.
The class target protein is in the kidney, and the efficacy of SGLT-2 inhibitors is dependent on renal function. Neither Invokana nor Farxiga can be prescribed to diabetics with severe renal impairment. Invokana's label permits it greater flexibility in the moderate renal impairment population as the lowest (100mg) dose can be prescribed to patients with a glomerular filtration rate (GFR) between 45 and 60 mL/min/1.73 m2, while Farxiga should not be prescribed at all if the GFR is below 60 mL/min/1.73m2.
In both cases, urinary tract infections are the most common side effect. Farxiga has an additional warning against its name that Invokana does not: An imbalance in bladder cancers was observed in clinical trials. It is not a black box warning, and there were too few cases to draw conclusions but it is never good to have the word cancer on your medicines package. Farxiga's post approval trial program will be designed to provide further clarity on the risk, but this will inevitably take years. The CHMP's assessment report discusses that Forxiga's tendency to cause infections may be causal of new cancers, or it may be that infections are resulting in an increased diagnosis rate of existing cancers. The implication is that a genuine cancer risk would also be shared by other SGLT-2 inhibitors.
You need to dig into the details to find meaningful differences between the two drugs but J&J have secured a slightly more favorable label. In terms of market performance, it is likely to be a close run affair as neither drug has a meaningful launch advantage and neither company has a meaningful presence or experience in diabetes.
For detailed analyses of clinical profiles and physician perception, see Decision Resources type 2 diabetes coverage.
For analysis of company strategy and positioning, see Decision Resources Pharmaview service.
Gideon Heap, M.Sc., is an analyst with the Pharmaview team at Decision Resources Group.