Acute-onset rhabdomyolysis secondary to sitagliptin and atorvastatin interaction

Myopathy with DPP-4 inhibitors and statins in the real world: investigating the likelihood of drug-drug interactions through the FDA adverse event reporting system

AIMS

To investigate the occurrence of myopathy with oral glucose-lowering drugs (OGLDs) and statins, with a focus on dipeptidyl peptidase-4 inhibitors (DPP4-is).

METHODS

The FDA adverse event reporting system (FAERS) was queried (2004-2016) to compare the proportion of adverse events with OGLDs, alone and in combination with statins, using the reporting odds ratio (ROR) with relevant 95% confidence interval (95%Cl), adjusted for sex, age and concomitant presence of other OGLDs/lipid-lowering drugs. Drug-drug interaction is claimed whenever the frequency of an event is enhanced by combination treatment. Consistency/robustness of findings was tested by applying additive/multiplicative models and accounting for competition bias (i.e., adverse events previously known to be associated with OGLDs were removed).

RESULTS

Over a 13-year period, we retrieved 142,888 cases of myopathy. The use of DPP4-is alone was not associated with higher reporting of myopathy (no. of cases = 4898; adjusted ROR = 1.00; 95%CI = 0.96-1.04), with the notable exclusion of vildagliptin (262; 1.64; 1.42-1.88). No increased occurrence emerged when used in combination with statins, with consistent findings from additive/multiplicative models for all DPP4-is. Likewise, no increased reporting was found for other OGLDs (28,964; 0.64; 0.62-0.67); data on the interaction with statins were consistent/robust across analyses only for sulfonylureas (the interaction is likely and biologically plausible) and sodium glucose cotransporter-2 inhibitors.

CONCLUSIONS

Real-world FAERS data do not raise concern for muscular toxicity with DPP4-is in combination with statins, making a drug interaction very unlikely.

Drug interactions of dipeptidyl peptidase 4 inhibitors involving CYP enzymes and P-gp efflux pump

Dipeptidyl peptidase 4 (DPP4) inhibitors are oral antidiabetic drugs approved to manage type 2 diabetes mellitus. Saxagliptin is a substrate of CYP3A4/5 enzymes while other DPP4 inhibitors such as sitagliptin, linagliptin, gemigliptin and teneligliptin are weak substrates of CYP3A4. DPP4 inhibitors have also been identified as substrates of P-gp. Hence, the drugs inhibiting or inducing CYP3A4/5 enzymes and/or P-gp can alter the pharmacokinetics of DPP4 inhibitors. This review is aimed to identify the drugs interacting with DPP4 inhibitors. The plasma concentrations of saxagliptin have been reported to be increased significantly by the concomitant administration of ketoconazole or diltiazem while no significant interactions between various DPP4 inhibitors and drugs like warfarin, digoxin or cyclosporine have been identified.

Sitagliptin and Simvastatin Interaction Causing Rhabdomyolysis and AKI

We report a case of rhabdomyolysis and severe acute kidney injury (AKI) requiring dialysis in a 69-year-old male who was recently started on sitagliptin while on chronic simvastatin therapy. This potential interaction is not included in the package insert for sitagliptin. A comprehensive literature review revealed six previous reports of rhabdomyolysis due to drug interaction between sitagliptin and statins including simvastatin, lovastatin, and atorvastatin. Of these six cases, only two had developed rhabdomyolysis-associated AKI, none of which were severe enough to require dialysis. As patients are commonly prescribed statins and sitagliptin for treatment of dyslipidemia and diabetes, health care professionals should be aware of this potential drug interaction and closely monitor their patients for signs and symptoms of rhabdomyolysis and AKI. This case highlights the importance of conducting further studies on the risk of muscular toxicity of sitagliptin especially when administered concurrently with statins.

Diabetes pharmacotherapy and effects on the musculoskeletal system

Persons with type 1 or type 2 diabetes have a significantly higher fracture risk than age-matched persons without diabetes, attributed to disease-specific deficits in the microarchitecture and material properties of bone tissue. Therefore, independent effects of diabetes drugs on skeletal integrity are vitally important. Studies of incretin-based therapies have shown divergent effects of different agents on fracture risk, including detrimental, beneficial, and neutral effects. The sulfonylurea class of drugs, owing to its hypoglycemic potential, is thought to amplify the risk of fall-related fractures, particularly in the elderly. Other agents such as the biguanides may, in fact, be osteo-anabolic. In contrast, despite similarly expected anabolic properties of insulin, data suggests that insulin pharmacotherapy itself, particularly in type 2 diabetes, may be a risk factor for fracture, negatively associated with determinants of bone quality and bone strength. Finally, sodium-dependent glucose co-transporter 2 inhibitors have been associated with an increased risk of atypical fractures in select populations, and possibly with an increase in lower extremity amputation with specific SGLT2I drugs. The role of skeletal muscle, as a potential mediator and determinant of bone quality, is also a relevant area of exploration. Currently, data regarding the impact of glucose lowering medications on diabetes-related muscle atrophy is more limited, although preclinical studies suggest that various hypoglycemic agents may have either aggravating (sulfonylureas, glinides) or repairing (thiazolidinediones, biguanides, incretins) effects on skeletal muscle atrophy, thereby influencing bone quality. Hence, the therapeutic efficacy of each hypoglycemic agent must also be evaluated in light of its impact, alone or in combination, on musculoskeletal health, when determining an individualized treatment approach. Moreover, the effect of newer medications (potentially seeking expanded clinical indication into the pediatric age range) on the growing skeleton is largely unknown. Herein, we review the available literature regarding effects of diabetes pharmacotherapy, by drug class and/or by clinical indication, on the musculoskeletal health of persons with diabetes.

Ameliorative potential of sitagliptin and/or resveratrol on experimentally-induced clear cell renal cell carcinoma

The aim of this study was to assess the effect of sitagliptin with or without resveratrol on carcinogen-induced clear cell renal cell carcinoma. Sixty male Wistar rats were divided into 6 equal groups as follows: control; clear cell renal cell carcinoma group; clear cell renal cell carcinoma+sitagliptin group; clear cell renal cell carcinoma+resveratrol group; clear cell renal cell carcinoma+carboxymethyl cellulose group and clear cell renal cell carcinoma+sitagliptin+resveratrol group. Blood urea, serum creatinine, creatinine clearance, urinary N-acetyl beta-d-glucosaminidase (NAG), gamma glutamyl transpeptidase (GGT) and urinary albumin excretion rate (UAER) were determined. Renal tissue antioxidant enzymes, lactate dehydrogenase (LDH), nuclear factor (erythroid-derived 2)-like 2 (Nrf2), heme oxygenase-1 (HO-1), transforming growth factor beta-1 (TGF-β1), tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6) and signal transducers and activators of transcription-3 (STAT3) were determined. Parts of the kidneys were subjected to histopathological and immunohistochemical examination for nuclear factor kappa B (p65). Sitagliptin and/or resveratrol induced significant improvement of the renal functions with significant increase in tissue antioxidant defenses and Nrf2/HO-1 content associated with significant decrease in tissue LDH, TGF-β1, TNF-α, IL-6 and STAT3 and alleviated the histopathological and immunohistochemical changes compared to the untreated clear cell renal cell carcinoma group. These effects were significant in sitagliptin/resveratrol combination group compared to the use of each of these drugs alone. In conclusion, sitagliptin/resveratrol combination might represent a beneficial therapeutic modality for amelioration of experimentally-induced clear cell renal cell carcinoma.