Dapagliflozin: Genital and urinary tract infections are common side effects of dapagliflozin that might potentially be porphyrinogenic.

Saxagliptin: No capacity for significant Cyp-interaction, and thus not for pharmacokinetic porphyrinogenicity. Urinary and upper respiratory tract infections are common side effects and potentially porphyrinogenic. The pharmacodynamic effects on glucose homeostasis with inhibition of pancreatic glucagon release are probably anti-porphyrinogenic. Dapagliflozin: Dapagliflozin is not an inducer or an inhibitor of CYP enzymes and no pharmacokinetic porphyrinogenic effects are suspected.

Saxagliptin: Aminoazabiocyclohexan carbonitrile. Dapagliflozin: Dapagliflozin is a selective and reversible inhibitor of sodium-glucose co-transporter 2 (SGLT2).

Saxagliptin: Saxagliptin is used in diabetes type 2 in combination with other orally administered anti-diabetics. Urinary and respiratory tract infections are common side effects and potentially porphyrinogenic. The very common hypoglycemic side effect noted in combination therapy with sulfonylureas is probably explained by enhanced effects on pancreatic insulin release and subsequent increase in tissue glucose uptake. It is thus not porphyrinogenic. Dapagliflozin: Dapagliflozin is an anti-diabetic indicated in adults with type 2 diabetes mellitus to improve glycaemic control. It is administered orally.

Saxagliptin: The metabolism of saxagliptin is primarily mediated by CYP 3A4/5. In in vitro studies, saxagliptin and its major metabolite neither inhibited CYP1A2, 2A6, 2B6, 2C9, 2C19, 2D6, 2E1, or 3A4, nor induced CYP1A2, 2B6, 2C9, or 3A4. Dapagliflozin: Dapagliflozin is bio transformed by UGT1A9 (present in liver and kidney) to dapagliflozin 3-O-glucuronide which is an inactive metabolite. CYP-mediated metabolism is only a minor clearance pathway but involves CYP1A1, 1A2, 2A6, 2C9, 2D6 and 3A4 (Kasichayanula 2014, SPC). In humans < 10% is metabolized by oxidative metabolism (Maranghi 2015). About 75 % is excreted in the urine and 21 % in the feaces, as metabolites (UpToDate). In an in vitro study dapagliflozin did not inhibit or induce human P450 enzymes (Obermeier 2010). An in vivo study found that dapagliflozin did not induce or inhibit CYP2C9 or CYP3A4 (Kasichayanula 2012). Interaction studies indicates that dapagliflozin does not affect the metabolism of CYP 2C9 and CYP 3A4 substrates (Kasichayanula 2014).