Pharmacokinetics comparison of two pegylated interferon alfa formulations in healthy volunteers.

BACKGROUND: Several countries have used pegylation technology to improve the pharmacokinetic properties of essential drugs. Recently, a novel interferon alfa-2b protein conjugated to four-branched 12 kDa polyethylene glycol molecules was developed jointly between Cuba and Brazil. The aim of this study was to compare the pharmacokinetic properties of BIP48 (pegylated interferon alfa-2b from Bio-Manguinhos/Fiocruz, Brazil) to those of PEGASYS® (commercially available pegylated interferon alfa-2a from Roche Pharmaceutical). METHODS: This phase I, single-centre, randomized, double-blind crossover trial enrolled 31 healthy male volunteers aged 19 to 35 who were allocated to two stages, either side of a 5-week wash-out period, with each arm lasting 14 consecutive days after subcutaneous administration of 180 µg of one formulation or the other (study or comparator). The main outcome variable was serum pegylated interferon concentrations in 15 samples collected during the course of the study and tested using an enzyme immunoassay. RESULTS: There were no differences between formulations in terms of magnitude or absorption parameters. Analysis of time parameters revealed that BIP48 remained in the body significantly longer than PEGASYS® (Tmax: 73 vs. 54 h [p = 0.0010]; MRT: 133 vs. 115 h [p = 0.0324]; ke: 0.011 vs. 0.013 h(-1) [p = 0.0153]; t1/2: 192 vs. 108 h [p = 0.0218]). CONCLUSION: BIP48 showed the expected pharmacokinetic profile for a pegylated product with a branched molecular structure. Compared to PEGASYS®, the magnitude absorption was similar, but time parameters were consistent with slower elimination. Further studies should be conducted to evaluate the clinical implications of these findings. A phase II-III repeated-dose clinical trial is ongoing to study these findings in patients with chronic hepatitis C virus infection. TRIAL REGISTRATION: This study is registered on the ClinicalTrials.gov platform (accession number NCT01889849 ). This trial was retrospectively registered in June 2013.

Immunogenicity and safety assessment of the Cuban recombinant hepatitis B vaccine in healthy adults.

Manufactures of biotechnological/biological products (including vaccines) frequently make changes to manufacturing processes of products both during development and after approval. In our case, a non-inferiority bridging study was carried out to demonstrate that changes in the production plant facilities of Cuban recombinant hepatitis B vaccine, Heberbiovac HB, did not affect the safety and immunogenicity of the vaccine. This controlled, randomized, doubled-blinded trial included 501 volunteers, aged between 20 and 64, who were given three doses of vaccine (20 microg HBsAg/mL) at month 0, 1, and 2. Four lots were evaluated (three corresponding to the new production facilities and a control one produced in the older facilities). One month after the third dose, were observed protective levels of anti-HBsAg in 97% of the subjects that concluded the study with a geometric mean antibody titer (GMT) of 931.18 IU/L. Normal values of body mass index (BMI), the younger ages, and being a female, were significantly related to a good antibody response. The vaccine was well tolerated. Pain at the injection site was the most commonly reported symptom. We conclude that Heberbiovac HB vaccine maintains its characteristics after the modifications carried out in the production plant facilities and both, lot obtained in previous facilities and in the new ones, are comparable in terms of safety and immunogenicity.

TNFalpha production in whole blood cultures from healthy individuals.

Tumor necrosis factor alpha (TNFalpha) is a major mediator of inflammatory responses and also plays a prominent role in bridging the innate and adaptive phases of immunity. In the present work we attempted to study TNFalpha production in endotoxin-stimulated blood of healthy individuals, and the inter-individual variability in TNFalpha production. For this study, we used diluted whole blood stimulated with lipopolysaccharide (LPS). The levels of the pro-inflammatory cytokine TNFalpha were measured by ELISA and by the L929 cytotoxicity bioassay in 16 and 18 healthy donors, respectively. There were highly significant inter-individual variations in the induced TNFalpha production. It is worth noting that there was no difference in sensitivity between ELISA and the cytotoxicity L929 bioassay. We concluded that whole blood culture is a sensitive method to determine the pro-inflammatory cytokine production in response to endotoxin stimuli in a relevant physiologic milieu. Our data indicate that this method provides appropriate information about the state of cellular immunity of the individual.