Allogeneic Growth Arrested Keratinocytes and Fibroblasts Delivered in a Fibrin Spray Accelerate Healing in Mohs Micrographic Surgery Wounds
May 2013 | Volume 12 | Issue 5 | Original Article | 558 | Copyright © May 2013
Leon Kircik MD,a-c Jaime E. Dickerson Jr PhD,d,e Christina Kitten,f
Kathy A. Weedon BS,d and Herbert B. Slade MDd,g
aMount Sinai Medical Center, New York, NY
bDepartment of Dermatology, Indiana University School of Medicine, Indianapolis, IN
cPhysicians Skin Care, PLLC, Louisville, KY
dHealthpoint Biotherapeutics, Fort Worth, TX
eDepartment of Cell Biology and Anatomy, gDepartment of Pediatrics, University of North Texas Health Science Center, Fort Worth, TX
fDermResearch, PLLC, Louisville, KY
Abstract
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.
J Drugs Dermatol. 2013;12(5):558-561.
INTRODUCTION
Second intention healing (SIH) is safe, well tolerated, provides for tumor surveillance, and is a cost-effective option for the handling of defects resulting from Mohs micrographic surgery (MMS). Healing in this way can also result in acceptable cosmetic outcomes.1-3 Requirements for successful SIH include the need for vascularized tissue underlying the defect and appropriate daily wound care (ie, cleansing, ointment or emollient application, followed by occlusion with a nonadherent dressing). A disadvantage of the SIH process is that it is somewhat slow, involving granulation and reepithelialization. SIH can be a time-consuming process requiring good patient compliance and frequent follow-up. Clearly, a method or procedure that could accelerate this process would be of benefit to patients and to clinicians.
Interest in the ability of autologous or allogeneic cells to stimulate and accelerate healing has provided the impetus for research on wounds of all types. For example, bullous ulcerations in patients with dystrophic epidermolysis bullosa have been treated with allogeneic fibroblasts and with allogeneic mesenchymal stem cells (MSCs) with some success.4,5 Acute wounds resulting from MMS have been treated with autologous MSCs.6 Bioengineered constructs that include allogeneic skin cells have been used for several years to treat chronic wounds.7,8
HP802-247 is a novel therapy currently in clinical development for the treatment of ulcers resulting from venous stasis. It is an allogeneic living cell suspension consisting of growth-arrested human keratinocytes (KC) and fibroblasts (FB) derived from neonatal foreskin delivered as a spray in a human fibrin matrix. HP802-247 is supplied as 2 cryopreserved components, a fibrinogen solution, and a suspension of cells (KC:FB ratio, 1:9) in a thrombin solution. After thawing, these components are sprayed sequentially on the wound bed, forming a thin fibrin matrix containing the 2 living but nonproliferating cell types. In vitro data show that these cells secrete several growth
