Shawn Cazzell
University of California, San Francisco
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Featured researches published by Shawn Cazzell.
Wound Repair and Regeneration | 2016
Robert S. Kirsner; Wolfgang Vanscheidt; David Keast; John Lantis; Cyaandi Dove; Shawn Cazzell; Mher Vartivarian; Matthias Augustin; William A. Marston; Nicholas D. McCoy; D. Innes Cargill; Tommy D. Lee; Jaime E. Dickerson; Herbert B. Slade
In 2012 we reported promising results from a phase 2 clinical trial of HP802‐247, a novel spray‐applied investigational treatment for chronic venous leg ulcers consisting of human, allogeneic fibroblasts and keratinocytes. We now describe phase 3 clinical testing of HP802‐247, its failure to detect efficacy, and subsequent investigation into the root causes of the failure. Two randomized, controlled trials enrolled a total of 673 adult outpatients at 96 centers in North America and Europe. The primary endpoint was the proportion of ulcers with confirmed closure at the end of 12 weeks of treatment. An investigation into the root cause for the failure of HP802‐247 to show efficacy in these two phase 3 trials was initiated immediately following the initial review of the North American trial results. Four hundred twenty‐one patients were enrolled in the North American (HP802‐247, 211; Vehicle 210) and 252 in the European (HP802‐247, 131; Vehicle 121) trials. No difference in proportion of closed ulcers at week 12 was observed between treatment groups for either the North American (HP802‐247, 61.1%; Vehicle 60.0%; p = 0.5896) or the European (HP802‐247, 47.0%; Vehicle 50.0%; p = 0.5348) trials. Thorough investigation found no likelihood that design or execution of the trials contributed to the failure. Variability over time during the trials in the clinical response implicated the quality of the cells comprising HP802‐247. Concordance between the two separate, randomized, controlled trials with distinct, nonoverlapping investigative sites and independent monitoring teams renders the possibility of a Type II error vanishingly small and provides strong credibility for the unexpected lack of efficacy observed. The most likely causative factors for the efficacy failure in phase 3 was phenotypic change in the cells (primarily keratinocytes) leading to batch to batch variability due to the age of the cell banks.
Advances in wound care | 2015
Shawn Cazzell; Darrell L. Lange; Jaime E. Dickerson; Herbert B. Slade
Objective: This study demonstrates that superior outcomes are possible when diabetic foot ulcers (DFU) are managed with tri-layer porcine small intestine submucosa (SIS). Approach: Patients with DFU from 11 centers participated in this prospective randomized controlled trial. Qualified subjects were randomized (1:1) to either SIS or standard care (SC) selected at the discretion of the Investigator and followed for 12 weeks or complete ulcer closure. Results: Eighty-two subjects (41 in each group) were evaluable in the intent-to-treat analysis. Ulcers managed with SIS had a significantly greater proportion closed by 12 weeks than for the Control group (54% vs. 32%, p=0.021) and this proportion was numerically higher at all visits. Time to closure for ulcers achieving closure was 2 weeks earlier for the SIS group than for SC. Median reduction in ulcer area was significantly greater for SIS at each weekly visit (all p values<0.05). Review of reported adverse events found no safety concerns. Innovation: These data support the use of tri-layer SIS for the effective management of DFU. Conclusion: In this randomized controlled trial, SIS was found to be associated with more rapid improvement, and a higher likelihood of achieving complete ulcer closure than those ulcers treated with SC.
Diabetes Care | 2017
Robert G. Frykberg; Ian L. Gordon; Alexander M. Reyzelman; Shawn Cazzell; Ryan H. Fitzgerald; Gary Rothenberg; Jonathan David Bloom; Brian Jude Petersen; David Robert Linders; Aksone Nouvong; Bijan Najafi
OBJECTIVE We conducted a multicenter evaluation of a novel remote foot-temperature monitoring system to characterize its accuracy for predicting impending diabetic foot ulcers (DFU) in a cohort of patients with diabetes with previously healed DFU. RESEARCH DESIGN AND METHODS We enrolled 132 participants with diabetes and prior DFU in this 34-week cohort study to evaluate a remote foot-temperature monitoring system (ClinicalTrials.gov Identifier NCT02647346). The study device was a wireless daily-use thermometric foot mat to assess plantar temperature asymmetries. The primary outcome of interest was development of nonacute plantar DFU, and the primary efficacy analysis was the accuracy of the study device for predicting the occurrence of DFU over several temperature asymmetry thresholds. RESULTS Of the 129 participants who contributed evaluable data to the study, a total of 37 (28.7%) presented with 53 DFU (0.62 DFU/participant/year). At an asymmetry of 2.22°C, the standard threshold used in previous studies, the system correctly identified 97% of observed DFU, with an average lead time of 37 days and a false-positive rate of 57%. Increasing the temperature threshold to 3.20°C decreased sensitivity to 70% but similarly reduced the false-positive rate to 32% with approximately the same lead time of 35 days. Approximately 86% of the cohort used the system at least 3 days a week on average over the study. CONCLUSIONS Given the encouraging study results and the significant burden of DFU, use of this mat may result in significant reductions in morbidity, mortality, and resource utilization.
International Wound Journal | 2018
Christian Bianchi; Shawn Cazzell; Dean Vayser; Alexander M. Reyzelman; Hasan Dosluoglu; Gregory Tovmassian
A randomised, controlled, multicentre clinical trial was conducted to evaluate the efficacy of dehydrated human amnion/chorion membrane (EpiFix) allograft as an adjunct to multilayer compression therapy for the treatment of non‐healing full‐thickness venous leg ulcers. We randomly assigned 109 subjects to receive EpiFix and multilayer compression (n = 52) or dressings and multilayer compression therapy alone (n = 57). Patients were recruited from 15 centres around the USA and were followed up for 16 weeks. The primary end point of the study was defined as time to complete ulcer healing. Participants receiving weekly application of EpiFix and compression were significantly more likely to experience complete wound healing than those receiving standard wound care and compression (60% versus 35% at 12 weeks, P = 0·0128, and 71% versus 44% at 16 weeks, P = 0·0065). A Kaplan–Meier analysis was performed to compare the time‐to‐healing performance with or without EpiFix, showing a significantly improved time to healing using the allograft (log‐rank P = 0·0110). Cox regression analysis showed that subjects treated with EpiFix had a significantly higher probability of complete healing within 12 weeks (HR: 2·26, 95% confidence interval 1·25–4·10, P = 0·01) versus without EpiFix. These results confirm the advantage of EpiFix allograft as an adjunct to multilayer compression therapy for the treatment of non‐healing, full‐thickness venous leg ulcers.
Wound Repair and Regeneration | 2017
Shawn Cazzell; Dean Vayser; Hau Pham; Jodi Walters; Alexander M. Reyzelman; Brian Samsell; Kimberly Dorsch; Mark Moore
This study compared the efficacy and safety of a human acellular dermal matrix (ADM), D‐ADM, with a conventional care arm and an active comparator human ADM arm, GJ‐ADM, for the treatment of chronic diabetic foot ulcers. The study design was a prospective, randomized controlled trial that enrolled 168 diabetic foot ulcer subjects in 13 centers across 9 states. Subjects in the ADM arms received one application but could receive one additional application of ADM if deemed necessary. Screen failures and early withdrawals left 53 subjects in the D‐ADM arm, 56 in the conventional care arm, and 23 in the GJ‐ADM arm (2:2:1 ratio). Subjects were followed through 24 weeks with major endpoints at Weeks 12, 16, and 24. Single application D‐ADM subjects showed significantly greater wound closure rates than conventional care at all three endpoints while all applications D‐ADM displayed a significantly higher healing rate than conventional care at Week 16 and Week 24. GJ‐ADM did not show a significantly greater healing rate over conventional care at any of these time points. A blinded, third party adjudicator analyzed healing at Week 12 and expressed “strong” agreement (κ = 0.837). Closed ulcers in the single application D‐ADM arm remained healed at a significantly greater rate than the conventional care arm at 4 weeks posttermination (100% vs. 86.7%; p = 0.0435). There was no significant difference between GJ‐ADM and conventional care for healed wounds remaining closed. Single application D‐ADM demonstrated significantly greater average percent wound area reduction than conventional care for Weeks 2–24 while single application GJ‐ADM showed significantly greater wound area reduction over conventional care for Weeks 4–6, 9, and 11–12. D‐ADM demonstrated significantly greater wound healing, larger wound area reduction, and a better capability of keeping healed wounds closed than conventional care in the treatment of chronic DFUs.
International Wound Journal | 2018
William Tettelbach; Shawn Cazzell; Felix Sigal; Joseph Caporusso; Patrick S. Agnew; Jason Hanft; Cyaandi Dove
The aim of this study was to determine the safety and effectiveness of dehydrated human umbilical cord allograft (EpiCord) compared with alginate wound dressings for the treatment of chronic, non‐healing diabetic foot ulcers (DFU). A multicentre, randomised, controlled, clinical trial was conducted at 11 centres in the United States. Individuals with a confirmed diagnosis of Type 1 or Type 2 diabetes presenting with a 1 to 15 cm2 ulcer located below the ankle that had been persisting for at least 30 days were eligible for the 14‐day study run‐in phase. After 14 days of weekly debridement, moist wound therapy, and off‐loading, those with ≤30% wound area reduction post‐debridement (n = 155) were randomised in a 2:1 ratio to receive a weekly application of EpiCord (n = 101) or standardised therapy with alginate wound dressing, non‐adherent silicone dressing, absorbent non‐adhesive hydropolymer secondary dressing, and gauze bandage roll (n = 54). All wounds continued to have appropriate off‐loading during the treatment phase of the study. Study visits were conducted for 12 weeks. At each weekly visit, the DFU was cleaned and debrided as necessary, with the wound photographed pre‐ and post‐debridement and measured before the application of treatment group‐specific dressings. A follow‐up visit was performed at week 16. The primary study end point was the percentage of complete closure of the study ulcer within 12 weeks, as assessed by Silhouette camera. Data for randomised subjects meeting study inclusion criteria were included in an intent‐to‐treat (ITT) analysis. Additional analysis was conducted on a group of subjects (n = 134) who completed the study per protocol (PP) (EpiCord, n = 86, alginate, n = 48) and for those subjects receiving adequate debridement (EpiCord, n = 67, alginate, n = 40). ITT analysis showed that DFUs treated with EpiCord were more likely to heal within 12 weeks than those receiving alginate dressings, 71 of 101 (70%) vs 26 of 54 (48%) for EpiCord and alginate dressings, respectively, P = 0.0089. Healing rates at 12 weeks for subjects treated PP were 70 of 86 (81%) for EpiCord‐treated and 26 of 48 (54%) for alginate‐treated DFUs, P = 0.0013. For those DFUs that received adequate debridement (n = 107, ITT population), 64 of 67 (96%) of the EpiCord‐treated ulcers healed completely within 12 weeks, compared with 26 of 40 (65%) of adequately debrided alginate‐treated ulcers, P < 0.0001. Seventy‐five subjects experienced at least one adverse event, with a total of 160 adverse events recorded. There were no adverse events related to either EpiCord or alginate dressings. These results demonstrate the safety and efficacy of EpiCord as a treatment for non‐healing DFUs.
International Wound Journal | 2018
William Tettelbach; Shawn Cazzell; Alexander M. Reyzelman; Felix Sigal; Joseph Caporusso; Patrick S. Agnew
A randomised, controlled multicentre clinical trial was conducted at 14 wound care centres in the United States to confirm the efficacy of dehydrated human amnion/chorion membrane allograft (dHACM) for the treatment of chronic lower extremity ulcers in persons with diabetes. Patients with a lower extremity ulcer of at least 4 weeks duration were entered into a 2‐week study run‐in phase and treated with alginate wound dressings and appropriate offloading. Those with less than or equal to 25% wound closure after run‐in were randomly assigned to receive weekly dHACM application in addition to offloading or standard of care with alginate wound dressings, for 12 weeks. A total of 110 patients were included in the intent‐to‐treat (ITT) analysis, with n = 54 in the dHACM group and n = 56 in the no‐dHACM group. Of the participants, 98 completed the study per protocol, with 47 receiving dHACM and 51 not receiving dHACM. The primary study outcome was percentage of study ulcers completely healed in 12 weeks, with both ITT and per‐protocol participants receiving weekly dHACM significantly more likely to completely heal than those not receiving dHACM (ITT—70% versus 50%, P = 0.0338, per‐protocol—81% versus 55%, P = 0.0093). A Kaplan–Meier analysis was performed to compare the time‐to‐healing performance with/without dHACM, showing a significantly improved time to healing with the use of allograft, log‐rank P < 0.0187. Cox regression analysis showed that dHACM‐treated subjects were more than twice as likely to heal completely within 12 weeks than no‐dHACM subjects (HR: 2.15, 95% confidence interval 1.30–3.57, P = 0.003). At the final follow up at 16 weeks, 95% of dHACM‐healed ulcers and 86% of healed ulcers in the no‐dHACM group remained closed. These results confirm that dHACM is an efficacious treatment for lower extremity ulcers in a heterogeneous patient population.
Foot & Ankle International | 2018
Shawn Cazzell; Jordan Stewart; Patrick S. Agnew; John Senatore; Jodi Walters; Douglas P. Murdoch; Alexander M. Reyzelman; Stuart D. Miller
Background: Failure of conservative management to reduce/eliminate symptoms of plantar fasciitis (PF) may indicate need for advanced treatments. This study reports Level 1 evidence supporting 3-month safety and efficacy of micronized dehydrated human amnion/chorion membrane (dHACM) injection as a treatment for PF. Methods: A prospective, single-blind, randomized controlled trial was conducted at 14 sites in the United States. Subjects were randomized to receive 1 injection, in the affected area, of micronized dHACM (n=73) or 0.9% sodium chloride placebo (n=72). Safety/efficacy assessments were conducted at 4 weeks, 8 weeks, 3 months, 6 months, and 12 months postinjection, using visual analog scale (VAS) for pain, Foot Function Index–Revised (FFI-R) score, and presence/absence of adverse events. Primary outcome was mean change in VAS score between baseline and 3 months expressed as difference in means for treatment versus control subjects. Secondary outcome was mean change in FFI-R score between baseline and 3 months expressed as difference in means for treatment versus control subjects. Results: Baseline VAS scores were similar between groups. At the 3-month follow-up, mean VAS scores in the treatment group were 76% lower compared with a 45% reduction for controls (P < .0001), FFI-R scores for treatment subjects had mean reduction of 60% versus baseline, whereas control subjects had mean reduction of 40% versus baseline (P = .0004). Of 4 serious adverse events, none were related to study procedures. Conclusion: Pain reduction and functional improvement outcomes were statistically significant and clinically relevant, supporting use of micronized dHACM injection as a safe and effective treatment for PF. Level of Evidence: Level I, prospective randomized trial.
ePlasty | 2016
Jodi Walters; Shawn Cazzell; Hau Pham; Dean Vayser; Alexander M. Reyzelman
Journal of Wound Care | 2016
Robert G. Frykberg; Shawn Cazzell; J. Arroyo-Rivera; Arthur Tallis; Alexander M. Reyzelman; F. Saba; L. Warren; B.C. Stouch; T.W. Gilbert