Preclinical pharmacokinetics and biodistribution of subcutaneously administered glycoPEGylated recombinant factor VIII (N8-GP) and development of a human pharmacokinetic prediction model

Essentials N8-GP is an extended half-life recombinant factor VIII (FVIII) for the treatment of hemophilia A. Subcutaneous (SC) FVIII dosing might reduce the treatment burden of prophylaxis. SC N8-GP has a favorable PK profile in animal models and disappears from skin injection sites. Combined animal (SC) and clinical (IV) data suggest that daily SC dosing may provide prophylaxis.

SUMMARY

Background N8-GP is an extended half-life recombinant factor VIII (FVIII) for the treatment of hemophilia A. Subcutaneous administration of FVIII may reduce the treatment burden of prophylaxis; however, standard FVIII products have low bioavailability after subcutaneous dosing in animals. Objective To evaluate the pharmacokinetics, effectiveness and local distribution of subcutaneously administered N8-GP in preclinical models and predict the human pharmacokinetic (PK) profile. Methods The pharmacokinetics of subcutaneously administered N8-GP were evaluated in FVIII knockout (F8-KO) mice and cynomolgus monkeys; a human PK prediction model in hemophilia A patients was developed. The hemostatic effect was evaluated in a tail vein bleeding model in F8-KO mice. The injection-site distribution and absorption of subcutaneously administered N8-GP were assessed in F8-KO mice by the use of temporal fluorescence imaging and immunohistochemistry. Results Subcutaneously administered N8-GP had a bioavailability, a first-order absorption rate and a half-life, respectively, of 24%, 0.094 h-1 and 14 h in F8-KO mice, and 26%, 0.33 h-1 and 15 h in cynomolgus monkeys. A dose-dependent effect of subcutaneously administered N8-GP on blood loss was observed in mice. A minimal amount of N8-GP was detected at the injection site 48-72 h after single or multiple dose(s) in F8-KO mice. Subcutaneously administered N8-GP was localized to the skin around the injection site, with time-dependent disappearance from the depot. PK modeling predicted that subcutaneously administered N8-GP at a daily dose of 12.5 IU kg-1 will provide FVIII trough levels of 2.5-10% in 95% of patients with severe hemophilia A. Conclusions Subcutaneously administered N8-GP may provide effective hemophilia A prophylaxis. A phase I clinical trial is underway to investigate this possibility.

Analgesic consumption trajectories in 8975 patients 1 year after fast-track total hip or knee arthroplasty

BACKGROUND

Persistent or increased long-term opioid consumption has previously been described following total hip- (THA) and knee arthroplasty (TKA). However, detailed information on postoperative analgesic consumption trajectories and risk factors associated with continued need of analgesics in fast-track THA and TKA is sparse.

METHODS

This is a descriptive multicentre study in primary unilateral fast-track THA or TKA with prospective data on patient characteristics and information on reimbursement entitled dispensed prescriptions of paracetamol, non-steroidal anti-inflammatory drugs, opioids, anticonvulsants and antidepressants 1 month preoperatively and 1 year postoperatively. Patients were stratified according to preoperative opioid use. Postoperative analgesic consumption trajectories were stratified as increased, decreased or no use compared to the preoperative period.

RESULTS

Of 8975 patients (4849 THA/4126 TKA), 33.9% had relevant reimbursed prescriptions 9-12 months postoperatively. Of 2136 (23.8%) patients with preoperative opioid use, 3.4% had unchanged opioid consumption at 9-12 months postoperatively. However, increased opioid consumption after 9-12 months occurred in 17.6 (TKA) and 10.2% (THA) compared to 9.9 and 6.3% in opioid-naive TKA and THA patients, respectively. Increased NSAID and paracetamol use was seen in 11.5 and 12.4% of all patients. Preoperative analgesic use (any), TKA, psychiatric disorder, tobacco abuse, cardiac disease and use of walking aids were associated with increased opioid consumption.

CONCLUSION

Continued and increased opioid and other analgesic use occur in a clinically significant proportion of fast-track TKA and THA patients 9-12 months postoperatively, suggesting treatment failure and need for early intervention. Preoperative risk assessment may allow identification of patients in risk of increased postoperative opioid consumption.

SIGNIFICANCE

We found a considerable fraction of patients with continued or increased opioid consumption 9-12 months after fast-track THA and TKA. Increase in opioid consumption was more frequent in preoperative opioid users than opioid-naive patients, but a pattern of increased analgesic consumption was present across all analgesics. Our data demonstrate a need for increased focus on long-term analgesic strategies and postoperative follow-up after THA and TKA, especially in preoperative opioid users.

[Sealing of the hepatic resection area using hemostat devices does not improve results of adequate surgery]

PURPOSE

In hepatic resections, there has been a high quality demand. The aim of this systematic clinical, prospective, unblinded unicenter observational study with two arms in an unselected patient cohort was to investigate whether hemostat device can significantly improve outcome in resective liver surgery, in particular, in high risk patients.

METHODS

All consecutive patients (mean age, 60.5 [range, 17 - 96] years) who underwent hepatic resection (ntotal = 770) were prospectively documented in a computer-based registry at a university hospital (tertiary center) over a time period of 10 years and retrospectively evaluated specifically with regard to the use (-/+; in daily practice and intraoperative decision-making) of hemostat device (Tissucol(®), n = 59/Tachocomb(®), n = 202/combination, n = 55) indicated (among others) by drainage volume, inflammatory parameters and rate of specific complications (nvalidated = 541 [100 %]).

RESULTS

Most frequently, (a-)/typical segmental resections were used: n = 192/90 (3-segment resection, only n = 38). 1) For the assignment of patients to the two different groups (-/+ hemostat device), weight loss and type of resection were found as significant factors (trend: ASA, cirrhosis), for the amount of drainage volume, ASA, sex, Karnofsky Performance Scale and also type of resections using independent distributed statistical tests (such as χ(2), U test [Mann/Whitney]; H test [Kruskal-Willis]; correlation coefficient by Spearman) - no impact: smoking, diabetes, BMI, ethanol. 2) Not taking into account these parameters, the use of hemostat device was characterized by an increased drainage volume (negative control < Tissucol = Tachocomb < combination). 3) Using multifactorial analysis of variance, it was found even under correction by the factors with significant impact elucidated in the single test that the application of hemostat device onto the hepatic resection area resulted unexpectedly rather in an increase than a decrease of the drainage volume but 4) under accompanying more pronounced increase of the white blood cell count (leucocytosis). 5) General and specific complications such as postoperative bleeding, biliary fistula and subhepatic abscess were not further lowered in a significant manner using hemostat device.

CONCLUSION

Adequate surgery in the operative management of hepatic resection area cannot further be improved or optimized using hemostat device. In this context, drainage volume may not be considered a sufficient rather an orienting parameter. However, there is an inflammatory response detectable most likely indicated by a(n un-)specific effusion and increase of white blood cell count, which can be interpreted as a) being characteristic for the problematic group of patients, in whom hemostat device was decided to be useful and was finally used in daily prectice, or b) reactive inflammation to foreign material.

Health-related quality of life in adolescents with inflammatory bowel disease depends on disease activity and psychiatric comorbidity

Adolescent patients with inflammatory bowel disease (IBD) show an increased risk for behavioral and emotional dysfunction. Health-related quality of life (HRQoL) is influenced by medical illnesses, as well as by psychiatric disorders, but for adolescents with IBD, the extent to which HRQoL is influenced by these two factors is unclear. For 47 adolescent IBD patients, we analyzed disease activity, HRQoL and whether or not a psychiatric disorder was present. Disease activity was estimated using pediatric Ulcerative Colitis Activity Index and pediatric Crohn's Disease Activity Index. The IMPACT-III and the EQ-5D were used to measure HRQoL and QoL, respectively. In addition, patient and parent diagnostic interviews were performed. 55.3 % patients fulfilled DSM-IV criteria for one or more psychiatric disorders. In all patients, psychiatric comorbidity together with disease activity contributed to a reduction in quality of life. Adolescents with IBD are at a high risk for clinically relevant emotional or behavioral problems resulting in significantly lower HRQoL. We conclude that accessible, optimally structured psychotherapeutic and/or psychiatric help is needed in adolescent patients with IBD.