The pharmacokinetics and safety of an intraoperative bupivacaine-collagen implant (XaraColl(®)) for postoperative analgesia in women following total abdominal hysterectomy

Minimizing pain in deer antler removal: Local anaesthetics in ZnO nanoparticle based collagen dressings as a promising solution

Antler removal in deer is a common practice for various purposes, including meat production and traditional medicine. However, the current industry practice using lidocaine as a local anesthetic has limitations, such as short duration of action and the potential for postoperative infections. In this study, we investigated the performance of a ZnO collagen nanocomposites loaded with local anesthetics to improve wound management and alleviate pain associated with antler removal in red deer. The research involved the preparation of collagen nanocomposites with local anesthetics and testing the drug release rates using in vitro drug release tests. Pharmacokinetic analysis was performed to evaluate the total drug release from the collagen matrix in red deer after velvet removal. Additionally, the analgesic efficacy of these collagen nanocomposite dressings was assessed after antler removal in red deer. Functionalized ZnO nanoparticles were incorporated into collagen fibers to enhance their mechanical stability and prolong drug release. The developed collagen nanocomposites aimed to slowly release local anesthetics and promote wound healing. The findings of this research could have significant implications for improving the pain management and wound healing associated with antler removal in deer. The results obtained from the in vitro drug release tests, pharmacokinetic analysis, and analgesic efficacy evaluations provide valuable insights into the understanding and development of novel approaches for antler removal procedures in red deer. The findings contribute to the advancement of knowledge in this field and lay the foundation for future implementation of improved techniques and protocols for antler removal.

Comparison of in vitro and in vivo Toxicity of Bupivacaine in Musculoskeletal Applications

The recent societal debate on opioid use in treating postoperative pain has sparked the development of long-acting, opioid-free analgesic alternatives, often using the amino-amide local anesthetic bupivacaine as active pharmaceutical ingredient. A potential application is musculoskeletal surgeries, as these interventions rank amongst the most painful overall. Current literature showed that bupivacaine induced dose-dependent myo-, chondro-, and neurotoxicity, as well as delayed osteogenesis and disturbed wound healing in vitro. These observations did not translate to animal and clinical research, where toxic phenomena were seldom reported. An exception was bupivacaine-induced chondrotoxicity, which can mainly occur during continuous joint infusion. To decrease opioid consumption and provide sustained pain relief following musculoskeletal surgery, new strategies incorporating high concentrations of bupivacaine in drug delivery carriers are currently being developed. Local toxicity of these high concentrations is an area of further research. This review appraises relevant in vitro, animal and clinical studies on musculoskeletal local toxicity of bupivacaine.

New peripheral nerve blocks and local anesthetics

PURPOSE OF REVIEW

To describe current developed regional blocks, their indications and clinical use. Furthermore, describe new local anesthetics recently introduced and the new agents in pipeline.

RECENT FINDINGS

There are multiple new blocks recently developed with the introduction of ultrasound to regional anesthesia and studies demonstrate effect in different surgical procedures. However, majority of the studies do not compare with gold standard and are relatively small to change clinical practice. Some of these blocks are: erector spinae plane block, infiltration between the popliteal artery and capsule of the posterior knee, pectoral nerve blocks, quadratus lumborum and transversus abdominis plane block. New local anesthetics and adjuvants have been developed in recent years. However, the studies with even with the oldest one introduced Exparel is currently questioned, large future studies are needed to determine efficacy and safety profile and compared with conventional local anesthetics.

SUMMARY

New regional block techniques and new local anesthetics have been introduced recently. However, the efficacy/safety and comparison to conventional techniques and local anesthetics are still needed. Future studies must focus on prolonging analgesia with least invasive regional technique and compare new local anesthetics with current ones.

Pharmacokinetics and Safety of INL-001 (Bupivacaine HCl) Implants Compared with Bupivacaine HCl Infiltration After Open Unilateral Inguinal Hernioplasty

Introduction

Surgical site infiltration with bupivacaine HCl results in short-lived analgesia for postsurgical pain and carries the risk of systemic bupivacaine toxicity due to accidental intravascular injection. INL-001 is a bupivacaine HCl collagen-matrix implant that provides extended delivery of bupivacaine directly at the site and avoids the risk of accidental injection. Here, we examine the pharmacokinetic (PK) and safety profile of INL-001 placement during unilateral open inguinal hernioplasty.

Methods

This multicenter, single-blind study (NCT03234374) enrolled patients undergoing open inguinal hernioplasty to receive three INL-001 implants, each containing 100 mg bupivacaine HCl (n = 34) or local infiltration of 0.25% bupivacaine HCl 175 mg (n = 16). Acetaminophen was provided in the postsurgical period and supplemented by opioids for breakthrough pain, as needed. PK blood samples were taken before surgery and up to 96 h after drug administration.

Results

INL-001 demonstrated a prolonged rate of absorption and clearance of bupivacaine compared with 0.25% bupivacaine HCl 175 mg, as demonstrated by a longer time to peak plasma concentration and terminal elimination half-life. Peak plasma concentration with INL-001 300 mg was comparable to bupivacaine HCl 175 mg and well below levels associated with systemic bupivacaine toxicity. The most common adverse events (AEs) in both groups were associated with general anesthesia and the postsurgical setting. No AE was related to the implant, including those associated with wound healing.

Conclusions

These findings demonstrate that INL-001 provides immediate and extended delivery of bupivacaine and is well tolerated in patients undergoing open inguinal hernioplasty with no adverse effect on wound healing.

Trial registration

Clinicaltrials.gov identifier, NCT03234374.

Electronic supplementary material

The online version of this article (10.1007/s12325-020-01565-x) contains supplementary material, which is available to authorized users.

Safety and Efficacy of Bupivacaine HCl Collagen-Matrix Implant (INL-001) in Open Inguinal Hernia Repair: Results from Two Randomized Controlled Trials

INTRODUCTION

Surgical site infiltration with bupivacaine results in short-lived analgesia. The MATRIX-1 and MATRIX-2 studies examined the efficacy and safety of the bioresorbable bupivacaine HCl collagen-matrix implant (INL-001) for postsurgical pain after open inguinal hernia repair. INL-001, designed to provide early and extended delivery of bupivacaine, provides prolonged duration of perioperative analgesia.

METHODS

In two phase 3 double-blind studies [MATRIX-1 (ClinicalTrials.gov identifier, NCT02523599) and MATRIX-2 (ClinicalTrials.gov identifier, NCT02525133)], patients undergoing open tension-free mesh inguinal hernia repair were randomized to receive 300-mg bupivacaine (three INL-001 100-mg bupivacaine HCl collagen-matrix implants) (MATRIX-1 n = 204; MATRIX-2 n = 213) or three placebo collagen-matrix implants (MATRIX-1 n = 101; MATRIX-2 n = 106) during surgery. Postsurgical medication included scheduled acetaminophen and as-needed opioids.

RESULTS

Patients who received INL-001 in both studies reported statistically significantly lower pain intensity (P ≤ 0.004; primary end point) and opioid analgesic use (P < 0.0001) through 24-h post-surgery versus those who received a placebo collagen-matrix. Patients who received INL-001 reported lower pain intensity through 72 h (P = 0.0441) for the two pooled studies. In both studies, more of the patients (28-42%) who received INL-001 used no opioid medication 0-24, 0-48, and 0-72 h post-surgery versus those who received a placebo collagen-matrix (12-22%). Among patients who needed opioid medication, patients receiving INL-001 used fewer opioids than those who received a placebo collagen-matrix through 24 h in both studies (P < 0.0001) and through 48 h in MATRIX-2 (P = 0.0003). Most adverse events were mild or moderate, without evidence of bupivacaine toxicity or deleterious effects on wound healing.

CONCLUSION

These findings indicate that INL-001 results in post-inguinal hernia repair analgesia that is temporally aligned with the period of maximal postsurgical pain and may reduce the need for opioids while offering a favorable safety profile.

TRIAL REGISTRATION

ClinicalTrials.gov identifiers, NCT02523599; NCT02525133.

FUNDING

Innocoll Pharmaceuticals. Plain language summary available for this article.

Endogenous opiates and behavior: 2013

This paper is the thirty-sixth consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2013 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior, and the roles of these opioid peptides and receptors in pain and analgesia; stress and social status; tolerance and dependence; learning and memory; eating and drinking; alcohol and drugs of abuse; sexual activity and hormones, pregnancy, development and endocrinology; mental illness and mood; seizures and neurologic disorders; electrical-related activity and neurophysiology; general activity and locomotion; gastrointestinal, renal and hepatic functions; cardiovascular responses; respiration and thermoregulation; and immunological responses.

A feasibility study to investigate the use of a bupivacaine-collagen implant (XaraColl) for postoperative analgesia following laparoscopic surgery

Background

XaraColl, a collagen-based implant that delivers bupivacaine to sites of surgical trauma, has been shown to reduce postoperative pain and use of opioid analgesia in patients undergoing open surgery. We therefore designed and conducted a preliminary feasibility study to investigate its application and ease of use for laparoscopic surgery.

Methods

We implanted four XaraColl implants each containing 50 mg of bupivacaine hydrochloride (200 mg total dose) in ten men undergoing laparoscopic inguinal or umbilical hernioplasty. Postoperative pain intensity and use of opioid analgesia were recorded through 72 hours for comparison with previously reported data from efficacy studies performed in men undergoing open inguinal hernioplasty. Safety was assessed for 30 days.

Results

XaraColl was easily and safely implanted via a laparoscope. The summed pain intensity and total use of opioid analgesia through the first 24 hours were similar to the values observed in previously reported studies for XaraColl-treated patients after open surgery, but were lower through 48 and 72 hours.

Conclusion

XaraColl is suitable for use in laparoscopic surgery and may provide postoperative analgesia in laparoscopic patients who often experience considerable postoperative pain in the first 24–48 hours following hospital discharge. Randomized controlled trials specifically to evaluate its efficacy in this application are warranted.