Pafolacianine for intraoperative molecular imaging of cancer in the lung: The ELUCIDATE trial.

OBJECTIVE: The study objective was to determine the clinical utility of pafolacianine, a folate receptor-targeted fluorescent agent, in revealing by intraoperative molecular imaging folate receptor α positive cancers in the lung and narrow surgical margins that may otherwise be undetected with conventional visualization. METHODS: In this Phase 3, 12-center trial, 112 patients with suspected or biopsy-confirmed cancer in the lung scheduled for sublobar pulmonary resection were administered intravenous pafolacianine within 24 hours before surgery. Participants were randomly assigned to surgery with or without intraoperative molecular imaging (10:1 ratio). The primary end point was the proportion of participants with a clinically significant event, reflecting a meaningful change in the surgical operation. RESULTS: No drug-related serious adverse events occurred. One or more clinically significant event occurred in 53% of evaluated participants compared with a prespecified limit of 10% (P < .0001). In 38 participants, at least 1 event was a margin 10 mm or less from the resected primary nodule (38%, 95% confidence interval, 28.5-48.3), 32 being confirmed by histopathology. In 19 subjects (19%, 95% confidence interval, 11.8-28.1), intraoperative molecular imaging located the primary nodule that the surgeon could not locate with white light and palpation. Intraoperative molecular imaging revealed 10 occult synchronous malignant lesions in 8 subjects (8%, 95% confidence interval, 3.5-15.2) undetected using white light. Most (73%) intraoperative molecular imaging-discovered synchronous malignant lesions were outside the planned resection field. A change in the overall scope of surgical procedure occurred for 29 of the subjects (22 increase, 7 decrease). CONCLUSIONS: Intraoperative molecular imaging with pafolacianine improves surgical outcomes by identifying occult tumors and close surgical margins.

One-year safety, healing and amputation rates of Wagner 3-4 diabetic foot ulcers treated with cryopreserved umbilical cord (TTAX01).

An open label, multicenter 16-week trial of cryopreserved human umbilical cord (TTAX01) was previously undertaken in 32 subjects presenting with a Wagner grade 3 or 4 diabetic foot ulcer, with 16 (50%) of these having confirmed closure following a median of one product application (previous study). All but two subjects (30/32; 94%) consented to participate in this follow-up study to 1-year postexposure. No restrictions were placed on treatments for open wounds. At 8-week intervals, subjects were evaluated for adverse events (AEs) and wound status (open or closed). Average time from initial exposure to end of follow-up was 378 days (range 343-433), with 29 of 30 (97%) subjects completing a full year. AEs were all typical for the population under study, and none were attributed to prior exposure to TTAX01. One previously healed wound re-opened, one previously unconfirmed closed wound remained healed, and nine new wound closures occurred, giving 25 of 29 (86.2%) healed in the ITT population. Three of the new closures followed the use of various tissue-based products. Three subjects whose wounds were healed required subsequent minor amputations due to osteomyelitis, one of which progressed to a major amputation (1/29; 3.4%). One additional subject underwent two minor amputations prior to healing. Overall, the study found TTAX01 to be safe in long-term follow-up and associated with both a low rate of major amputation and a higher than expected rates of healing.

An open-label trial of cryopreserved human umbilical cord in the treatment of complex diabetic foot ulcers complicated by osteomyelitis.

Clinical trials of potential new therapies for diabetic foot ulcers rarely enroll patients whose wounds extend to muscle, fascia, or bone with clinical and radiographic evidence of underlying osteomyelitis. An open-label, multicenter trial of cryopreserved human umbilical cord (TTAX01) was undertaken in 32 subjects presenting with such complex wounds with a mean duration of 6.1 ± 9.0 (range: 0.2-47.1) months and wound area at screening of 3.8 ± 2.9 (range: 1.0-9.6) cm2 . Aggressive surgical debridement at baseline resulted in 17 minor amputations and an increase in mean wound area to 7.4 ± 5.8 (range: 1.1-28.6) cm2 . All subjects were placed on systemic antibiotics for at least 6 weeks in conjunction with baseline application of TTAX01. Repeat applications were made at no less than 4-week intervals over the 16-week trial. Initial closure occurred in 18 of 32 (56%) wounds, with 16 (50%) of these having confirmed closure in 16 weeks with a median of one-product application. Cases with biopsy confirmed osteomyelitis (n = 20) showed initial closure in 12 (60%) wounds and confirmed closure in 10 (50%) wounds. Four of the five ulcers presenting as recurrences experienced confirmed closure. Mean overall time to healing was 12.8 ± 4.3 weeks. Mean wound area reduction from baseline was 91% for all wounds. Of the 16 wounds without confirmed closure during the 16-week treatment period, five (31.3%) achieved 99-100% wound area reduction by their final visit. The product was well tolerated. Two minor amputations occurred during the study period due to recurrent or persistent osteomyelitis; however, there were no major amputations.

Baseline factors affecting closure of venous leg ulcers.

OBJECTIVE: The objective of this study was to characterize factors associated with closure of venous leg ulcers (VLUs) in a pooled analysis of subjects from three randomized clinical trials. METHODS: Closure of VLUs after treatment with HP802-247, an allogeneic living cell therapy consisting of growth-arrested human keratinocytes and fibroblasts, vs standard therapy with compression bandaging was evaluated in three phase 3 clinical trials of similar design. Two trials enrolled subjects with VLUs ranging from 2 cm2 to 12 cm2 in area with 12-week treatment periods; the third trial enrolled subjects with VLUs between >12 cm2 and ≤36 cm2 with a 16-week treatment period. The first trial went to completion but failed to demonstrate a benefit to therapy with HP802-247 compared with placebo, and because of this, the remaining trials were terminated before completion. On the basis of no differences in outcomes between groups, subjects from both HP802-247 and control groups were pooled across all three studies. Cox proportional hazards regression analysis was employed to evaluate factors associated with VLU closure. RESULTS: This analysis included data from 716 subjects with VLU. Factors evaluated for association with healing included age, gender, race, diabetes, glycated hemoglobin level, body mass index, treatment (HP802-247 vs compression alone), and ulcer characteristics including location and area and duration at baseline. In an initial model including all of these putative factors, the following were significant at the P < .10 level: diagnosis of diabetes mellitus, gender, wound location (ankle or leg), baseline wound area, and wound duration at baseline. In a final model including only these factors, all but diabetes mellitus were significant at the P < .05 level. Effect sizes were as follows (hazard ratio [95% confidence interval]): female gender (1.384 [1.134-1.690]), wound location on the leg (1.490 [1.187-1.871]), smaller wound area at baseline (0.907 [0.887-0.927]), and shorter wound duration at baseline (0.971 [0.955-0.987]). CONCLUSIONS: Factors associated with VLU lesions including location, area, and duration were important predictors of healing. Women were more likely than men to achieve wound closure. Factors including body mass index, the presence of diabetes mellitus, and higher concentrations of glycated hemoglobin were not significant independent predictors of wound closure in this analysis.

The Management of Diabetic Foot Ulcers with Porcine Small Intestine Submucosa Tri-Layer Matrix: A Randomized Controlled Trial.

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.

Anti-inflammatory Effects of Clostridial Collagenase Results from In Vitro and Clinical Studies.

BACKGROUND: Digestion of collagen with clostridial collagenase (CC) produces peptides that can induce cellular responses consistent with wound healing in vivo. However, nonhealing human wounds are typically in a state of chronic inflammation. We evaluated the effects of CC on markers of inflammation in cell culture and wound fluid from diabetic patients. METHODS: Lipopolysaccharide-induced release of tumor necrosis factor-α and interleukin-6 from interferon-γ-activated THP-1 monocytes was measured in the presence or absence of CC or CC collagen digests. In the clinical study, 17 individuals with mildly inflamed diabetic foot ulcers were randomized to receive CC ointment (CCO) or hydrogel. Weekly assessments included wound appearance and measurements. Wound exudate was collected at baseline and at 2 and 4 weeks of treatment. A multiplex assay was used to measure levels of analytes, including those associated with inflammation and with inflammation resolution. RESULTS: Lower levels of tumor necrosis factor-α and interleukin-6 were found in media of cells cultured with CC or CC digests of collagen type I or III than for untreated lipopolysaccharide controls (P < .05). Clinically, CCO and hydrogel resulted in improvement in wound appearance and a decrease in mean wound area. The CCO, but not the hydrogel, was found to increase the level of analytes associated with resolution of inflammation while decreasing those associated with inflammation. There was a general correlation between resolution of inflammation and healing. CONCLUSIONS: These results support a hypothesis that debridement with CCO is associated with decreased inflammation and greater progress toward healing.

Cryo-Induced Thermal Wounds: A Human Acute Wound Model.

INTRODUCTION: Clinical models are invaluable in studying wound healing. Challenges in studying human wounds include heterogeneity of patients and wounds, as well as prolonged study time, resulting in high costs. Animal models are an efficient method to study wound healing, but often lack correlation with human acute wound healing. Human wound models can be created using sharp instruments, suction, acids, heat and cold. In this observational study, we propose a practical human acute wound model where partial thickness wounds are induced by cryosurgery to create wounds that could facilitate wound healing research and development. METHODS: On forearms of 8 healthy adult volunteers, freeze injuries were induced using liquid nitrogen spray delivered onto a target area of a 1 cm circular opening at a distance from the cryo-device to the skin of 0.5-1 cm. Several freeze-thaw time cycles were implemented by administering pulses ranging from 3 to 12 seconds. Clinical evaluation was performed at a 24-hour follow-up period. Blister roofs were histologically analyzed by a blinded dermatophathologist. Clinical assessment of time to heal was determined. RESULTS: Freeze-times greater than 5 seconds caused a majority of subjects to develop blisters, and freeze-times greater than 8 seconds resulted in uniform blister formation. Consistent histology of full thickness necrotic epidermis with intact detached basement membrane with minimal acute neutrophilic inflammatory infiltrate was observed in all blister specimens examined. The 8-second freeze-time group had a time to heal of 13-14 days, while the 12-second freeze-time group required 3 weeks to heal. After healing, an area of hypopigmented skin and slightly hypertrophic scarring remained. DISCUSSION: This novel cryo-induced wound model is a potential simple, efficient and reliable model for studying the dynamic processes involved in acute wound healing and to aid in the development of new wound healing therapies. Clinicaltrials.gov identifier: NCT01253135.

The effect of ankle range of motion on venous ulcer healing rates.

Limitation of ankle movement may contribute to calf muscle pump failure, which is thought to contribute to venous leg ulcer formation, which affects nearly 1 million Americans. We therefore wished to study ankle movement in patients with venous leg ulcers and its effect on healing. Using goniometry, we measured baseline ankle range of motion in venous leg ulcer patients from a Phase 2 dose-finding study of an allogeneic living cell bioformulation. Two hundred twenty-seven patients were enrolled in four active treatment groups and one standard-care control group, all receiving compression therapy. Goniometry data from a control group of 49 patients without venous disease, from a previous study, was used for comparison. We found patients with active venous leg ulcers had significantly reduced ankle range of motion compared with the control group (p = 0.001). After 12 weeks of therapy, baseline ankle range of motion was not associated with healing, as there was no significant difference between healed and nonhealed groups, suggesting that ankle range of motion is not important in venous leg ulcer healing or, more likely, is overcome by compression. However, patients with venous ulcers located on the leg (as opposed to the ankle) had significantly higher ankle range of motion for plantar flexion and inversion (p = 0.021 and p = 0.034, respectively) and improved healing with both cell bioformulation and standard care (p = 0.011), suggesting that wound location is an important variable for ankle range of motion as well as for healing outcomes.

Three phase III randomized controlled trials of topical resiquimod 0.01-percent gel to reduce anogenital herpes recurrences.

Resiquimod, a Toll-like receptor 7 and 8 agonist, stimulates production of cytokines that promote an antigen-specific T helper type 1 acquired immune response. Animal and phase II human trials showed posttreatment efficacy in reducing recurrent herpes lesion days and/or time to first recurrence. Three phase III randomized, double-blind, vehicle-controlled trials of topical resiquimod to reduce anogenital herpes recurrences were conducted in healthy adults with ≥4 recurrences within the prior year. Participants applied resiquimod 0.01% gel or vehicle gel 2 times per week for 3 weeks to each recurrence for 12 months. Trials 1 and 2 had 2:1 resiquimod-vehicle randomization. Trial 3 had 1:1:1 randomization for resiquimod and 500 mg valacyclovir orally twice daily for 5 days (RESI-VAL), resiquimod and oral placebo (RESI-PLA), and vehicle and oral placebo (VEH-PLA). The median time to first recurrence was similar for resiquimod and vehicle (trial 1, 60 and 56 days, P=0.7; trial 2, 54 and 48 days, P=0.47; trial 3, 51 [RESI-VAL], 55 [RESI-PLA], and 44 [VEH-PLA] days, P=not significant [NS]). The median time to healing of initial treated recurrence was longer for resiquimod (trial 1, 18 compared to 10 days, P<0.001; trial 2, 19 compared to 13 days, P=0.16; trial 3, 14 [RESI-VAL], 16 [RESI-PLA], and 8 [VEH-PLA] days, P<0.001). In trials 1 and 2, moderate to severe erythema and erosion/ulceration at the application site were more common in resiquimod recipients. In conclusion, no posttreatment efficacy of resiquimod 0.01% gel was observed. Increased application site reactions and initial recurrence healing time are consistent with resiquimod-induced cytokine effects.

Clinical outcomes associated with serial sharp debridement of diabetic foot ulcers with and without clostridial collagenase ointment.

OBJECTIVE: Fifty-five subjects with diabetes mellitus type 1 or 2 and a neuropathic, nonischemic foot ulcer were enrolled into this randomized, controlled, multicenter trial designed to examine the effects of debridement with clostridial collagenase ointment (CCO) used in conjunction with serial sharp debridement for a period of 6 weeks. METHODS: Serial sharp debridement without adjunctive CCO was used in the control group. Various standard care therapies thought to support debridement by endogenous proteases were selected at the discretion of the investigators for use in the control group. The primary outcome measure of this trial was the percent change in ulcer area from baseline at the end of the debridement/treatment period (EOT) and at the end of an additional 6 weeks of follow-up (EOS). Secondary objectives were to assess wound status at EOT and EOS using a standardized wound assessment tool, and to compare the average time to closure for ulcers debrided with serial sharp debridement with and without adjunctive CCO. RESULTS: Wound area decreased relative to baseline for both the CCO group (-68%, -61%) and the control group (-36%, -46%) at EOT and EOS, respectively. While the inter-group differences did not reach statistical significance, wound area was significantly decreased from baseline at both EOT and EOS for the CCO (P < 0.001) but not for the control group. Wound status scores (scale range 8 to 40) improved for both groups during treatment (CCO: -3.5, control: -3.2) and follow-up (CCO: -5.3, control: -6.4). No differences were observed in the number of sharp debridements (CCO: 3.7, control: 4.0). Median time to closure for wounds that healed was 6 weeks for CCO and 8 weeks for control. On average, ulcers treated with serial sharp debridement plus adjunctive CCO decreased in size more rapidly than ulcers treated without adjunctive CCO debridement. No safety issues were identified based on a review of reported adverse events. CONCLUSION: These results suggest there is more to wound debridement than meets the eye, and establish a foundation for larger, confirmatory studies.

Clinical and economic assessment of diabetic foot ulcer debridement with collagenase: results of a randomized controlled study.

BACKGROUND: Despite significant advances, the treatment of diabetic foot ulcers (DFUs) remains a major therapeutic challenge for clinicians, surgeons, and other health care professionals. There is an urgent need for new strategies with clinically effective interventions to treat DFUs to reduce the burden of care in an efficient and cost-effective way. OBJECTIVE: This randomized trial evaluated and compared the clinical effectiveness, tolerability, and costs of clostridial collagenase ointment (CCO) debridement to that of debridement using saline moistened gauze (SMG) and selective sharp debridement for the treatment of DFUs. METHODS: Randomized, controlled, parallel group, multicenter, open-label, 12-week study of 48 patients with neuropathic DFUs randomized to 4 weeks of treatment with either CCO or SMG after baseline surgical debridement. The primary end point was the condition of the ulcer bed at the end of treatment as measured using a standardized wound assessment tool. Secondary end points were the percentage of reduction in wound area and therapeutic response rates. Adverse events were monitored for the tolerability analysis. In addition, a comparative cost-effectiveness analysis was performed from the perspective of the Centers for Medicare and Medicaid Services as a payer. RESULTS: Both the CCO and SMG groups had significantly improved wound assessment scores after 4 weeks of treatment (CCO, -2.5, P = 0.007; SMG, -3.4, P = 0.006). Only CCO treatment resulted in a statistically significant decrease from baseline in the mean wound area at the end of treatment (P = 0.0164) and at the end of follow-up (P = 0.012). In addition, the CCO group exhibited a significantly better response rate at the end of follow-up compared with the SMG group (0.92 vs 0.75, P < 0.05). Reported adverse events were similar between the 2 treatment groups. None of the reported adverse events were considered to be related to treatment. The economic analysis indicated that the direct mean costs per responder in the physician office setting of care were $832 versus $1042 for the CCO group versus the SMG group, whereas the direct mean costs per responder in the hospital outpatient department setting were $1607 versus $1980. CONCLUSIONS: CCO treatment provides equivalent debridement of DFUs similar to SMG while fostering better progress toward healing as measured by decreasing wound area over time and improved response rates at the end of follow-up. In addition, CCO yields a more favorable cost-effectiveness ratio in both the physician office and hospital outpatient department settings of care. ClinicalTrials.gov identifier: NCT01056198.

Durability of healing from spray-applied cell therapy with human allogeneic fibroblasts and keratinocytes for the treatment of chronic venous leg ulcers: a 6-month follow-up.

Patients who participated in a Phase 2 trial of HP802-247 for venous leg ulcers were invited to participate in this 24-week follow-up study to assess the durability of healing, document additional ulcer closures, and evaluate posttreatment safety. Consent was given by 90% (206/228), with 80% (183/228) completing all visits. Blinding was retained from the previous trial in which subjects had been randomized to vehicle or one of four cell therapy regimens. Visits were every 8 weeks. Among the 183 subjects, 43% (21/49) previously treated with cells and entering follow-up with an open wound achieved closure, compared with 35% (7/20) previously treated with vehicle, while 10% (11/106) and 17% (3/18), respectively, experienced reopening of a previously closed wound. Subjects previously treated with cells closed more open wounds than those previously treated with vehicle (OR 1.39, 95% CI 0.47-4.10; p = 0.739), and less subjects with a previously closed wound reopened (OR 0.65, CI 0.16-2.60; p = 0.821); however, these findings were not statistically significant. At the final visit, the difference in proportion of subjects with wounds closed continued to favor the best dose from the prior trial (83% closed vs. 58%, delta 25%). Follow-up beyond 12 weeks is necessary to evaluate the full benefit of this therapy, as treatment with cells may provide stimulus toward healing that persists for up to several weeks following the last application. The results show that the greater proportional benefit achieved by HP802-247 relative to standard care after 12 weeks of treatment persists over a meaningful timeframe.

Allogeneic growth arrested keratinocytes and fibroblasts delivered in a fibrin spray accelerate healing in Mohs micrographic surgery wounds.

OBJECTIVES: To determine the effectiveness of HP802-247 compared with bacitracin ointment in healing wounds resulting from Mohs micrographic surgery. METHODS: Open-label, randomized pilot study conducted at a single center. Subjects were randomized to either HP802-247 (5M cells/mL) applied weekly or bacitracin ointment applied daily. Treatment continued for up to 12 weeks or complete wound closure. Primary efficacy was effectiveness as measured by the Investigator's Global Assessment of Healing (IGAH) scale. Secondary outcomes included median time to healing, investigator- and subject-scored signs and symptoms, and an assessment of scar by the investigator at 16 weeks postsurgery. RESULTS: All subjects achieved favorable outcomes within the study period; however, these were reached more quickly for the HP802-247 group than for bacitracin. At 3 weeks postsurgery, healing was assessed as very effective for 75% of subjects in the HP802-247 group compared with 50% for bacitracin. Median time to closure was 24.5 days for HP802-247 and 29 days for bacitracin. Scores for signs and symptoms and scar were similar for both groups but, in general, were numerically better for HP802-247. CONCLUSION: In this small pilot study, HP802-247 was found to provide a modest, incremental benefit in the healing of Mohs micrographic surgery wounds, suggesting that the healing of uncomplicated acute wounds may be slightly accelerated without enhancement of scarring.

The influence of patient and wound variables on healing of venous leg ulcers in a randomized controlled trial of growth-arrested allogeneic keratinocytes and fibroblasts.

OBJECTIVE: To examine patient and wound variables presumed to influence healing outcomes in the context of therapeutic trials for chronic venous leg ulcers. METHODS: This double-blind, vehicle-controlled study was conducted with randomized assignment to one of four cell therapy dose groups (n = 46, 43, 44, 45) or vehicle control (n = 50). A 2-week run-in period was used to exclude rapid healers and those with infection or uncontrolled edema. This was a multicenter (ambulatory, private, hospital-based and university-based practices, and wound care centers in North America) study. Adults ≥ 18 years old with chronic venous insufficiency associated with an uninfected venous leg ulcer (2-12 cm(2) area, 6-104 weeks' duration) were included in the study. Excluded were pregnant or lactating women, wounds with exposed muscle, tendon or bone, patients unable to tolerate compression bandages, or patients who had exclusionary medical conditions or exposure to certain products. Exclusion during run-in included patients with infection, uncontrolled severe edema or with healing rates ≥ 0.349 cm/2 wk. Screen fail rate was 37% (134/362), and the withdrawal rate was~10% (23 of 228). Growth-arrested neonatal dermal fibroblasts and keratinocytes were delivered via pump spray in a fibrin sealant-based matrix, plus a foam dressing and four-layer compression bandaging. Treatment continued for 12 weeks or until healed, whichever occurred first. Patient demographic and wound-related variables were evaluated for influence on complete wound healing in all patients, as well as the subsets of treated and control patients. RESULTS: Wound duration (P = .004) and the presence of specific quantities of certain bacterial species (P < .001) affected healing in the vehicle group, while healing in the cell-treated groups was influenced by wound duration (P = .012), wound area (P = .026), wound location (P = .011), and specific quantities of certain bacterial species (P = .002). Age, sex, race, diabetes, HbA1C, peripheral neuropathy, and serum prealbumin did not significantly affect healing. Body mass index was positively associated with healing in cell-treated patients. CONCLUSIONS: Wound duration is a quantifiable surrogate for one or more undefined variables that can have a profound negative effect on venous leg ulcer healing. Although cell therapy overcame barriers to healing, the only specific barrier identified was the presence of certain bacterial species. Interventional trials of potentially effective new therapies can be most informative when patients with suspected barriers to healing are included. The specific measurement of candidate barriers such as microbial pathogens, wound inflammatory state, and fibroblast function should be considered in future randomized trials to improve our understanding of the basis for chronicity.

Cell Persistence of Allogeneic Keratinocytes and Fibroblasts Applied in a Fibrin Matrix to Acute, Full Thickness Wounds.

HP802-247 is a living cell suspension of cultured allogeneic growth-arrested human male keratinocytes and fibroblasts (1:9 ratio), intended for spray application to chronic wounds. In this study, a small wound was created on the arms of 28 healthy female volunteers (3-mm punch), followed by a single application of HP802-247. At each subsequent week for 8 weeks, a punch excision of the wounds was performed on a cohort of three subjects. Excised specimens were analyzed for allogeneic fibroblast and keratinocyte DNA determined by Y-chromosome short-tandem repeats using PCR amplification followed by capillary electrophoresis, a method with estimated sensitivity of 1 male cell in a background of 8,000 female cells. A complete haplotype attributable to HP802-247 fibroblasts was detected in three of three samples at 1 week, with one partial and one complete fibroblast haplotype detected at 2 weeks, and one partial keratinocyte haplotype detected at 3 weeks postapplication. The findings indicate that HP802-247 can be expected to persist in an acute wound bed for up to 2 weeks postapplication.

Spray-applied cell therapy with human allogeneic fibroblasts and keratinocytes for the treatment of chronic venous leg ulcers: a phase 2, multicentre, double-blind, randomised, placebo-controlled trial.

BACKGROUND: Many patients with venous leg ulcers do not heal with standard care. HP802-247 is a novel spray-applied cell therapy containing growth-arrested allogeneic neonatal keratinocytes and fibroblasts. We compared different cell concentrations and dosing frequencies of HP802-247 for benefit and harm when applied to chronic venous leg ulcers. METHODS: We enrolled adult outpatients from 28 centres in the USA and Canada with up to three ulcers, venous reflux confirmed by doppler ultrasonography, and adequate arterial flow in this phase 2, double-blind, randomised, placebo-controlled trial if at least one ulcer measured 2-12 cm(2) in area and had persisted for 6-104 weeks. Patients were randomly assigned by computer-generated block randomisation in a 1:1:1:1:1 ratio to 5·0×10(6) cells per mL every 7 days or every 14 days, or 0·5×10(6) cells per mL every 7 days or every 14 days, or to vehicle alone every 7 days. All five groups received four-layer compression bandages. The trial sponsor, trial monitors, statisticians, investigators, centre personnel, and patients were masked to treatment allocation. The primary endpoint was mean percentage change in wound area at the end of 12 weeks. Analyses were by intention to treat, excluding one patient who died of unrelated causes before first treatment. This trial is registered with ClinicalTrials.gov NCT00852995. FINDINGS: 45 patients were assigned to 5·0×10(6) cells per mL every 7 days, 44 to 5·0×10(6) cells per mL every 14 days, 43 to 0·5 ×10(6) cells per mL every 7 days, 46 to 0·5 ×10(6) cells per mL every 14 days, and 50 to vehicle alone. All required visits were completed by 205 patients. The primary outcome analysis showed significantly greater mean reduction in wound area associated with active treatment compared with vehicle (p=0·0446), with the dose of 0·5 ×10(6) cells/mL every 14 days showing the largest improvement compared with vehicle (15·98%, 95% CI 5·56-26·41, p=0·0028). Adverse events were much the same across all groups, with only new skin ulcers and cellulitis occurring in more than 5% of patients. INTERPRETATION: Venous leg ulcers can be healed with a spray formulation of allogeneic neonatal keratinocytes and fibroblasts without the need for tissue engineering, at an optimum dose of 0·5×10(6) cells per mL every 14 days. FUNDING: Healthpoint Biotherapeutics.