Co-administration of liraglutide with insulin detemir demonstrates additive pharmacodynamic effects with no pharmacokinetic interaction.

AIM: To compare the pharmacokinetic (PK) [area under the curve (AUC0(-)24 (h), C(max))] and pharmacodynamic (PD) (AUC(GIR) 0(-)24 (h), GIR(max)) properties of single-dose insulin detemir in the presence or absence of steady-state liraglutide (1.8 mg dose) in subjects with type 2 diabetes to determine whether co-administration affected the PK and PD profiles of either therapeutic agent. METHODS: Following a 3-week washout of oral antidiabetic agents (OADs) other than metformin, PK and PD assessments during three euglycaemia clamps were conducted: day 1 following a single dose of insulin detemir alone (0.5 U/kg), day 22 after 3 weeks of once-daily liraglutide with weekly dose escalation to 1.8 mg daily, and day 36 after 2 weeks of steady-state liraglutide maintenance at the 1.8 mg dose following co-administration with a single dose of insulin detemir (0.5 U/kg). RESULTS: The study population (N = 33; age 49.6 (±8.5) years) had diabetes for an average of 6.5 (±4.1) years, BMI 33 (±6.4) kg/m², FPG 9.7 (±1.6) mmol/l and HbA1c 8.3% (±0.9). PK: The PK profiles of insulin detemir were similar with and without steady-state liraglutide. Liraglutide did not affect AUC or C(max) of insulin detemir and vice versa. The 90% confidence intervals (CIs) for ratios of insulin detemir AUC [1.03; CI (0.97, 1.09)] and C(max) [1.05; CI (0.98, 1.13)] and liraglutide AUC [0.97; CI (0.87, 1.08)] and C(max) [1.03, CI (0.93, 1.13)] were all within the no-effect boundary (0.80, 1.25) (bioequivalence criterion). A stable mean insulin detemir concentration with and without liraglutide was maintained at the end of the 24-h PK sampling period. PD: The sum of AUC(GIR) for liraglutide (1982 mg/kg) and insulin detemir (1058 mg/kg) when given alone was similar to that obtained when the two were co-administered (2947 mg/kg). No serious adverse events were reported and no adverse events led to study withdrawal. CONCLUSION: Co-administration of liraglutide 1.8 mg at steady state and insulin detemir produces an additive glucose-lowering effect without affecting the PK profile of either therapeutic agent suggesting that the addition of insulin detemir to patients treated with liraglutide will not require titration algorithms different from when insulin is added to OADs. The co-administration of insulin detemir and liraglutide was well tolerated.

Resuscitation in massive obstetric haemorrhage using an intraosseous needle.

A 38-year-old woman experienced a massive postpartum haemorrhage 30 minutes after emergency caesarean delivery. The patient became severely haemodynamically compromised with an unrecordable blood pressure. Rapid fluid resuscitation was limited by the capacity of the intravenous cannula in place at the time and inability to establish additional vascular access using conventional routes in a timely manner. An intraosseous needle was inserted in the proximal humerus at the first attempt and administration of resuscitation fluid by this route subsequently enabled successful placement of further intravenous lines. Blood and blood products were deployed in conjunction with intra-operative cell salvage and transoesophageal Doppler cardiac output monitoring was used to assess adequacy of volume replacement. Haemorrhage control was finally achieved with the use of recombinant factor VIIa and hysterectomy.

Pharmacokinetics of trimetrexate and dapsone in AIDS patients with Pneumocystis carinii pneumonia.

The objective of this study was to determine the pharmacokinetics of trimetrexate and dapsone in AIDS patients with moderate to severe pneumocystis pneumonia. Trimetrexate, leucovorin, and dapsone were administered for 21 +/- 3 days in the following doses: trimetrexate glucuronate, 45 mg/m2; leucovorin, 20 mg/m2; and dapsone, 100 mg daily. The pharmacokinetics of trimetrexate, dapsone, and dapsone's metabolite, monoacetyldapsone, were determined at three separate periods over the course of treatment. Serial blood samples were obtained over 24 hours after dosing and analyzed for trimetrexate, dapsone, and monoacetyldapsone, and pharmacokinetic parameters were determined. The mean parameters obtained for the early, mid-, and late collection periods were the following: trimetrexate: t1/2 = 8.29, 9.15, 10.00 hr; AUC = 16.85, 22.38, 24.49 mg.hr/l; CI = 5.58, 4.14, 3.96 l/hr, respectively. DDS: t1/2 = 14.99, 16.59, 15.13 hr; AUC = 30.60, 35.29, 36.08 mg.hr/l; CI = 3.82, 3.49, 3.01 l/hr, respectively. Monoacetyldapsone: t1/2 = 20.25, 18.66, 16.32 hr; AUC = 24.05, 24.06, 23.86 mg.hr/l, respectively. No statistically significant changes in pharmacokinetics for trimetrexate or dapsone were observed over the 21 +/- 3 day course of treatment. The results suggest that there are no major interactions between trimetrexate and dapsone when administered together in acutely ill patients.

Phase I study of AG 331, a novel thymidylate synthase inhibitor, in patients with refractory solid tumors.

PURPOSE: This was a phase I study of AG 331 to determine systemic tolerance and pharmacokinetics following single and multiple escalating intravenous doses. METHODS: The study was an open-label phase I trial that was divided into two components. In phase IA (single dose), six dose levels from 12.5 to 225 mg/m2 were administered to 18 patients (3 at each dose level) and serial blood samples were collected for 72 h. Upon achieving satisfactory pharmacologic parameters, the multiple dosing component (phase IB) was initiated. Six dose levels from 50 to 800 mg/m2 per day were administered for 5 consecutive days to 18 patients. Pre- and postdose blood samples were obtained on days 1-4 and serial blood samples were collected over 24 h following dose 5. Nonhematologic and hepatic toxicities were assessed, serum AG 331 concentrations were measured and pharmacokinetic parameters determined. RESULTS: Other than fatigue, no severe toxicities were encountered in phase IA. Liver toxicity was manifested by elevations in transaminase first noted at multiple doses of 200 mg/m2 per day for 5 days. Fever and malaise but no myelosuppression were noted. The mean terminal t1/2 following single doses was significantly shorter than the t1/2 following multiple dosing (6.8 vs 9.9 h) and clearance was significantly faster following single doses than following multiple dosing (81.7 vs 30.4 l/h), but no significant difference in Vd was noted. CONCLUSIONS: The dose-related toxicity profile precludes further clinical development at this time. The pharmacokinetics of AG 331 following single and multiple doses showed significant differences.

Permeability of pure enantiomers of ketorolac through human cadaver skin.

The permeability of pure enantiomers of ketorolac acid, a potent non-narcotic analgesic, through human cadaver skin was evaluated. The melting temperature of each enantiomer was 20 degrees C higher than that of the racemic compound. As expected, the solubility of the racemic compound in water and isopropyl alcohol/water/isopropyl myristate (IPA/water/IPM, 50:50:1.5) was roughly 2 times higher than that of the enantiomers. The permeability of the enantiomers through poly(ethylenevinyl acetate) (EVA) synthetic membrane and human cadaver skin was determined with a side-by-side diffusion cell. The skin flux of the racemic compound was about 1.5 times higher than those of the enantiomers. On the other hand, no significant differences in the intrinsic permeability coefficient of the racemic compound and the enantiomers in the EVA membrane and human cadaver skin was observed. An excellent agreement between the predicted and experimental flux ratio of the racemic compound and enantiomer in the EVA membrane and cadaver skin was observed. The IPA/water/IPM (50:50:1.5) provided the highest in vitro skin flux of the S enantiomer among the three vehicle formulations studied. The skin flux of the active pure S enantiomer was ca. 34% higher than that of the impure S enantiomer in the racemic mixture. Furthermore, about 14% intersubject variability in the in vitro skin flux of the S enantiomer was observed. The required skin flux of the S enantiomer as calculated from the pharmacokinetic parameters was about 32 micrograms/cm2/h from a 25 cm2 transdermal patch, which was readily achievable from the IPA/water/IPM (50:50:1.5) ternary vehicle system.

Liraglutide's safety, tolerability, pharmacokinetics, and pharmacodynamics in pediatric type 2 diabetes: a randomized, double-blind, placebo-controlled trial.

BACKGROUND: The prevalence of type 2 diabetes (T2D) in youth is increasing. Treatment options beyond metformin and insulin are needed. The safety, tolerability, pharmacokinetics, and pharmacodynamics of liraglutide once daily in youth (10-17 years old) with T2D were investigated in a randomized, double-blind, placebo-controlled trial. SUBJECTS AND METHODS: Youth treated with diet/exercise alone or with metformin and having a hemoglobin A1c (HbA1c) level of 6.5-11% were randomized to liraglutide (n=14) or placebo (n=7). Starting at 0.3 mg/day, doses were escalated weekly to 0.6, 0.9, 1.2, and 1.8 mg/day (or placebo equivalent) for 5 weeks. RESULTS: Nineteen participants completed the trial. Baseline characteristics were similar between groups, with mean (SD) values for age of 14.8 (2.2) years, weight of 113.2 (35.6) kg (range, 57-214 kg), diabetes duration of 1.7 (1.4) years, and HbA1c level of 8.1% (1.2%). No serious adverse events (AEs), including severe hypoglycemia, occurred. Transient gastrointestinal AEs were most common at lower liraglutide doses during dose escalation. No significant changes in safety and tolerability parameters occurred. There was no evidence of pancreatitis or lipase elevations above three times the upper normal limit; calcitonin levels remained within the normal range. For liraglutide 1.8 mg, mean half-life was 12 h, and clearance was 1.7 L/h. After 5 weeks, the decline in HbA1c level was greater with liraglutide versus placebo (-0.86 vs. 0.04%, P=0.0007), whereas mean body weight remained stable (-0.50 vs. -0.54 kg, P=0.9703). CONCLUSIONS: Liraglutide was well tolerated in youth with T2D, with safety, tolerability, and pharmacokinetic profiles similar to profiles in adults.

Effect of vehicles and penetration enhancers on the in vitro and in vivo percutaneous absorption of methotrexate and edatrexate through hairless mouse skin.

PURPOSE: Low-dose methotrexate (MTX) is approved for the treatment of recalcitrant rheumatoid arthritis (RA). The objective of this study was to determine the effect of vehicles and penetration enhancers on the percutaneous absorption of MTX and its analog edatrexate (EDAM), and develop transdermal (TD) delivery systems of the drugs for the treatment of RA. METHODS: From previously published pharmacokinetic parameters with low-dose MTX therapy, and considering a 50 cm2 diffusional area, the target steady state in vitro TD flux for MTX was calculated to be 35 micrograms/cm2/hr. Modified Franz diffusion chambers and hairless mouse skin were used for in vitro skin permeation studies. Hairless mice were used for in vivo studies. Delivered amounts of MTX and EDAM were determined by assaying the receiver phase fluid (or blood) with validated reversed phase HPLC methods. RESULTS: Intrinsic partition coefficient of MTX was low (log P = -1.2). Target MTX fluxes of > or = 35 micrograms/cm2/hr were achievable only with 1-15% (v/v) Azone in propylene glycol (PG). Flux of EDAM (85 micrograms/cm2/hr) was higher than MTX from an isopropyl alcohol (IPA)-5% (v/v) Azone system. Clinically significant steady state in vivo blood concentration of MTX and EDAM was achieved using delivery systems containing > or = 2.5% Azone in PG. Area under the drug concentration-time curves (AUC0-24 hr) for MTX were 2379 and 3534 ng*hr/ml from PG-2.5% Azone and PG-7.5% Azone systems respectively. AUC0-24 hr of EDAM was 6893 ng*hr/ml using a PG-2.5% Azone system. CONCLUSIONS: Results of this study show the feasibility of using a transdermal delivery system of MTX and EDAM for the treatment of rheumatoid arthritis.

High-performance liquid chromatographic method for the determination of a novel thymidylate synthase inhibitor, AG 331, in human serum.

AG 331 is a novel thymidylate synthase inhibitor currently in Phase I clinical trial. To determine the pharmacokinetic parameters of AG 3331 in human subjects, a suitable analytical method was developed using high-performance liquid chromatography. Serum and urine samples were prepared using both solid-phase extraction and solvent extraction. Either 4,4'-diaminodiphenyl sulfone or benz[cd]indole-2(1H)-one were used as internal standards for the method. A reversed-phase C18 analytical column completely resolved the drug and internal standard peaks from non-specific substances present in biological matrix. The method was validated for precision, accuracy, and reproducibility in serum and was linear over a concentration range of 50-2000 ng/ml, with a limit of detection of 20.0 ng/ml and a quantifiable limit of 50 ng/ml.