Clinical effects of exposure to DPP-4 inhibitors as reported to the National Poison Data System

Compliance with the DPP-4 inhibitors dose adjustment recommendations based on renal function in a population database

OBJECTIVE

To examine the prescription pattern of the different dipeptidyl peptidase-4 inhibitors (DPP4is), depending on the estimated glomerular filtration rate (eGFR) under real-world clinical practice conditions.

METHOD

This was a descriptive, observational study using a population database (SIDIAP Catalonia). Subjects diagnosed with T2DM with kidney function assessed and on active treatment with DPP4is were enrolled. Patients were included at the time of the measurement of eGFR (CKD-epi) and were monitored for 6 months after enrolment. For each subject, the prescribed daily dose (PDD) of DPP4i, the theoretical dose according to the degree of renal failure established by the recommendations in the summary of product characteristics (DDD-adj), and the PDR ratio (PDD/DDD-adj) were estimated. A subject was considered overtreated if his/her RDR was greater than 1.2 (>20%).

RESULTS

The study sample consisted of 72,135 subjects with a mean age of 69.7 (±11.6) years and 55.9% males. The proportion of patients overtreated varied depending on the type of DPP4i and the renal function stage. Overall, overdosage was recorded in 7.15% of all DPP4i treatments. In advanced stages (IIIb, IV, and V), overdosage was much higher (36.8% for all DPP4is, and 58.7% if linagliptin is excluded).

DISCUSSION

Under real-world clinical practice conditions, more than one third of T2DM patients with advanced renal failure were overdosed with DPP4is because the doses were not adequately adjusted to the glomerular filtration rate of each patient.

Biowaiver Monograph for Immediate-Release Solid Oral Dosage Forms: Sitagliptin Phosphate Monohydrate

Sitagliptin is an antihyperglycemic drug used in adults for the treatment of diabetes Type 2. Literature data and in-house experiments were applied in this monograph to assess whether methods based on the Biopharmaceutics Classification System (BCS) could be used to assess the bioequivalence of solid immediate-release (IR) oral dosage forms containing sitagliptin phosphate monohydrate, as an alternative to a pharmacokinetic study in human volunteers. The solubility and permeability characteristics of sitagliptin were reviewed according to the BCS, along with dissolution, therapeutic index, therapeutic applications, pharmacokinetics, pharmacodynamic characteristics, reports of bioequivalence (BE) / bioavailability problems, data on interactions between the drug and excipients and other data germane to the subject. All data reviewed in this monograph unambiguously support classification of sitagliptin as a BCS Class 1 drug. In light of its broad therapeutic index and lack of severe adverse effects, the clinical risks associated with moderately supraoptimal doses were deemed inconsequential, as were the risks associated with moderately suboptimal doses. Taking all evidence into consideration, it was concluded that the BCS-based biowaiver can be implemented for solid IR oral drug products containing sitagliptin phosphate monohydrate, provided (a) the test product is formulated solely with excipients commonly present in solid IR oral drug products approved in ICH or associated countries and used in amounts commonly applied in this type of product, (b) data in support of the BCS-based biowaiver are obtained using the methods recommended by the WHO, FDA, EMA or ICH and (c) the test product and the comparator product (which is the innovator product in this case) meet all in vitro dissolution specifications provided in the WHO, FDA, EMA or ICH guidance.

Toxicology of Medications for Diabetes Mellitus

Medications used to treat diabetes mellitus are heterogeneous, with widely differing safety profiles in therapeutic use and in overdose. Insulin overdose may produce severe and prolonged hypoglycemia. Sulfonylurea poisoning should be treated with octreotide, sparing intravenous dextrose where possible. Acute metformin overdose may lead to life-threatening acidosis with elevated lactate concentrations, which may require hemodialysis. Glucagon-like peptide 1 agonists and dipeptidyl peptidase 4 inhibitors are benign in overdose in diabetic patients but may produce profound hypoglycemia in nondiabetic patients. Euglycemic diabetic ketoacidosis may develop in critically ill patients taking sodium-glucose co-transporter 2 inhibitors.

Compliance with the DPP-4 inhibitors dose adjustment recommendations based on renal function in a population database

OBJECTIVE

To examine the prescription pattern of the different dipeptidyl peptidase-4 inhibitors (DPP4is), depending on the estimated glomerular filtration rate (eGFR) under real-world clinical practice conditions.

METHOD

This was a descriptive, observational study using a population database (SIDIAP Catalonia). Subjects diagnosed with T2DM with kidney function assessed and on active treatment with DPP4is were enrolled. Patients were included at the time of the measurement of eGFR (CKD-EPI) and were monitored for 6 months after enrolment. For each subject, the prescribed daily dose (PDD) of DPP4i, the theoretical dose according to the degree of renal failure established by the recommendations in the summary of product characteristics (DDD-adj), and the PDR ratio (PDD/DDD-adj) were estimated. A subject was considered overtreated if his/her RDR was greater than 1.2 (>20%).

RESULTS

The study sample consisted of 72,135 subjects with a mean age of 69.7 (±11.6) years and 55.9% males. The proportion of patients overtreated varied depending on the type of DPP4i and the renal function stage. Overall, overdosage was recorded in 7.15% of all DPP4i treatments. In advanced stages (IIIb, IV and V), overdosage was much higher (36.8% for all DPP4is, and 58.7% if linagliptin is excluded).

DISCUSSION

Under real-world clinical practice conditions, more than one third of T2DM patients with advanced renal failure were overdosed with DPP4is because the doses were not adequately adjusted to the glomerular filtration rate of each patient.

Effects of dipeptidyl peptidase-4 inhibitors on transforming growth factor-β1 signal transduction pathways in the ovarian fibrosis of polycystic ovary syndrome rats

Aim

Examine the effects of dipeptidyl peptidase‐4 (DPP4) inhibitor Sitagliptin on the transforming growth factor‐β1 (TGF‐β1) signal transduction pathway in polycystic ovary syndrome (PCOS) rats with ovarian fibrosis.

Methods

Thirty rats were divided randomly into the PCOS model group, Sitagliptin treatment group and blank control group. Dehydroepiandrosterone was administered to the model group and treatment group to establish the models. Then, the phenotype of rats was recorded, and the serum sex hormone levels were measured. The pathological structures of the rat ovaries were observed. The protein and mRNA expression levels of DPP4, connective tissue growth factor (CTGF), TGF‐β1 and Smad2/3 in the ovaries were analyzed.

Results

There was no statistically difference in fasting body weight and blood glucose among the three groups before Sitagliptin treatment (P > 0.05). The fasting blood glucose level was significantly decreased after the administration of Sitagliptin (P < 0.05). The level of testosterone in the model group was reduced remarkably after Sitagliptin treatment (P < 0.001). The protein expression levels of DPP4, CTGF and TGF‐β1 in the ovarian stroma were lower in the treatment group than in the model group (P < 0.01, P < 0.001, P < 0.05). The mRNA levels of DPP4, CTGF and TGF‐β1 in the model group also greatly declined after Sitagliptin treatment (P < 0.05, P < 0.001, P < 0.01).

Conclusion

The DPP4 inhibitor Sitagliptin lowers fasting blood glucose, relieves the high androgen state of PCOS rats and delays the process of ovarian fibrosis, which may be related to reducing the levels of factors related to the TGF‐β1/Smad2/3 signaling pathway.