A randomized phase 1 pharmacokinetic trial comparing the potential biosimilar PF-05280014 with trastuzumab in healthy volunteers (REFLECTIONS B327-01).

AIMS: The pharmacokinetic (PK) similarity between PF-05280014, a proposed trastuzumab biosimilar, trastuzumab sourced from European Union (trastuzumab-EU) or from United States (trastuzumab-US) was evaluated. Safety and immunogenicity were also assessed. METHODS: In this phase 1, double-blind trial (NCT01603264), 105 healthy male volunteers were randomized 1:1:1 to receive a single 6 mg kg(-1) intravenous dose of PF-05280014, trastuzumab-EU, or trastuzumab-US, and evaluated for 70 days. Drug concentration-time data were analyzed by non-compartmental methods. PK similarity for the comparisons of PF-05280014 to each of trastuzumab-EU and trastuzumab-US, and trastuzumab-EU to trastuzumab-US were determined using the standard 80.00% to 125.00% bioequivalence criteria. RESULTS: Baseline demographics for the 101 subjects evaluable for PK were similar across all arms. The three products exhibited similar PK profiles with target-mediated disposition. The 90% CIs for the ratios of Cmax , AUC (0 , t last) and AUC(0,∞) were within 80.00% to 125.00% for all three pairwise comparisons. Adverse events (AEs) were similar across all arms with treatment-related AEs reported by 71.4%, 68.6% and 65.7% subjects in the PF-05280014, trastuzumab-EU, and trastuzumab-US arms, respectively. The most common AEs were infusion-related reactions, headache, chills, pyrexia and nausea. The AE term 'pyrexia' was numerically greater in the PF-05280014 arm. All post-dose samples, except 1, tested negative for anti-drug antibodies (ADA). CONCLUSIONS: This study demonstrates PK similarity among PF-05280014, trastuzumab-EU and trastuzumab-US. The safety and immunogenicity profiles observed for the three products in this study are consistent with previous reports for trastuzumab.

Pharmacokinetic interactions between lersivirine and zidovudine, tenofovir disoproxil fumarate/emtricitabine and abacavir/lamivudine.

BACKGROUND: To investigate pharmacokinetic interactions associated with coadministration of lersivirine with zidovudine, tenofovir disoproxil fumarate (DF)/emtricitabine (Truvada(®)) or abacavir/lamivudine (Epzicom(®)/Kivexa(®)). METHODS: Three Phase I, open, crossover studies with two (studies 1 and 3) or three (study 2) treatment periods were conducted in healthy individuals. In study 1, individuals received zidovudine and placebo or zidovudine and lersivirine on days 1-14. In study 2, individuals received lersivirine and tenofovir DF/emtricitabine, lersivirine and placebo or tenofovir DF/emtricitabine and placebo on days 1-10. In study 3, individuals received abacavir/lamivudine only in period 1 (5 days) and abacavir/lamivudine and lersivirine in period 2 (10 days). Blood samples were taken on days 1-14 (study 1) or day of final dose (studies 2 and 3) and analysed using high performance liquid chromatography/dual mass spectrometry. Pharmacokinetic parameters were calculated by standard non-compartmental methods. RESULTS: When coadministered with lersivirine, zidovudine exposure increased by 35%, and exposure of its metabolite zidovudine-glucuronide decreased by 19%. Following coadministration of lersivirine and tenofovir DF/emtricitabine, tenofovir exposure increased by 30%, and lersivirine exposure decreased by 12%. Coadministration of lersivirine and abacavir/lamivudine increased abacavir exposure by 27% and decreased lamivudine exposure by 8%. Adverse events were predominantly mild in these Phase I studies. CONCLUSIONS: Coadministration of lersivirine with zidovudine, tenofovir DF/emtricitabine or abacavir/lamivudine influenced the systemic exposure of all nucleoside reverse transcriptase inhibitor agents investigated (except for lamivudine; emtricitabine pharmacokinetics were not assessed). Changes were not considered clinically meaningful for zidovudine and abacavir. The clinical relevance of the effect on tenofovir pharmacokinetics is currently unknown.

Pharmacokinetics and pharmacodynamics of figitumumab, a monoclonal antibody targeting the insulin-like growth factor 1 receptor, in healthy participants.

This study determined the pharmacokinetics (PK) of figitumumab and its effects on insulin-like growth factor (IGF) axis-related biomarkers, following a single intravenous dose (10 [n = 16] and 20 [n = 12] mg/kg) in healthy adults. Serial blood sampling for PK and biomarkers was conducted up to 84 days postdose. A dose increase from 10 to 20 mg/kg led to 1.9- and 2.4-fold increases in mean C(max) and AUC∞, respectively. Median disposition half-life was 21.1 and 27.8 days at 10 and 20 mg/kg, respectively. At 10 and 20 mg/kg, figitumumab increased total IGF-1, free IGF-1, IGF binding protein (IGFBP)-3, and insulin by 4.1- and 4.8-, 8.3- and 12.1-, 2.4- and 2.9-, and 7.3- and 9.8-fold, respectively; increases were sustained throughout the 84-day period. There was a slight and transient elevation in IGF-2. Mean plasma glucose increased by 18% and 16% at 10 and 20 mg/kg, respectively. Most treatment-related adverse events were mild in severity; the most common included dry eye (n = 9) and ocular hyperemia (n = 9) in the 20-mg/kg group. No antidrug antibodies were detected. Overall, figitumumab (10 or 20 mg/kg) demonstrated PK properties typical of IgG2 antibodies and produced substantial and sustained increases in IGF-1 (total and free), IGFBP-3, and insulin.