Repurposing Ophthalmologic Timolol for Dermatologic Use: Caveats and Historical Review of Adverse Events.

Ophthalmic timolol solution is increasingly being repurposed as a topical therapeutic for a variety of dermatologic diseases, including pyogenic granulomas, infantile hemangiomas, and chronic wounds. There are no published guidelines or protocols for use in these indications in adults, and the dermatologic community may not be familiar with adverse events that have been extensively documented relating to its ophthalmic use. We review the evidence available relating to adverse events to topical timolol use to evaluate its safety in dermatologic applications and to alert clinicians to screening and monitoring that is needed when repurposing this drug for dermatologic use. The majority of serious adverse events associated with ophthalmic timolol were reported in the first 7 years of use, between 1978 and 1985, of which most common were cardiovascular and respiratory events, but also included 32 deaths. The available evidence suggests that ophthalmic timolol safety profiling may have been incomplete prior to widespread use. Recent clinical trials for dermatologic indications have focused on documenting efficacy and have not had rigorous monitoring for potential adverse events. Topical timolol may be safe and effective for the treatment of various dermatologic conditions in patients whose medical histories have been carefully reviewed for evidence of pre-existing cardiac or pulmonary disease and are monitored for potential adverse events. Despite the wide use of timolol in ophthalmologic practice, safe dermatologic repurposing requires recognition of the potential for facilitated systemic absorption though the skin and appreciation of its history of adverse events.

Beta-adrenergic antagonist for the healing of chronic diabetic foot ulcers: study protocol for a prospective, randomized, double-blinded, controlled and parallel-group study.

BACKGROUND: Diabetic foot ulcers (DFUs) are the most common cause of leg amputations and their management is extremely challenging. Despite many advances and expensive therapies, there has been little success in improving outcomes of DFUs. In prior work our laboratory has examined the effects of beta-adrenergic antagonists (ßAAs) on skin and skin-derived cells. We have shown that ßAAs enhance the rate of keratinocyte migration, promote angiogenesis, and hasten wound healing in scratch wounds in vitro, in animal wound models, and in anecdotally reported cases of chronic wounds that healed successfully after topical application of the ßAA timolol. Thus, we propose to test timolol directly on DFUs to determine if it improves healing above the current standard of care (SOC). This study will examine the efficacy and safety of topically applied beta-antagonist Timoptic-XE® (timolol maleate ophthalmic gel forming solution) in subjects with DFUs. METHODS/DESIGN: This is a phase two, randomized, double-blinded, controlled, and parallel-group clinical trial with two treatment arms, SOC plus topical Timoptic-XE® and SOC plus a non-biologically active gel (hydrogel, as placebo drug). Study subjects with a DFU will be selected from the Veterans Affairs Northern California Health Care System (VANCHCS). Study duration is up to 31 weeks, with three phases (screening phase for two weeks, active phase for up to 12 weeks, with an additional second consecutive confirmatory visit after 2 weeks, and follow-up phase comprising monthly visits for 4 months). Subjects will apply daily either the topical study drug or the placebo on the foot ulcer for 12 weeks or until healed, whichever comes first. Measurements of wound size and other data will be collected at baseline, followed by weekly visits for 12 weeks, and then a monthly follow-up period. DISCUSSION: This is a clinical translation study, moving the investigators' pre-clinical laboratory research into a translational study in which we will analyze clinical outcomes to assess for safety and estimate the efficacy of a topical beta-antagonist in healing of DFUs. The results from this trial may establish new treatment paradigms and safety profile for DFU treatment. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03282981. Registered on June 14th, 2018.

Absorption and Safety of Topically Applied Timolol for Treatment of Chronic Cutaneous Wounds.

Objective: There are no safety or absorption studies to guide topical timolol therapy for treatment of chronic wounds. This study was undertaken to address this gap. Approach: A prospective, observational, cross-sectional comparative study of timolol plasma levels in patients after topical administration to a chronic wound, compared with levels in patients after timolol ocular administration for the indication of glaucoma. Results: There was no statistically significant difference in the average plasma level of timolol in wound as compared with glaucoma patients. No bradycardia or wheezing was observed after administration. Innovation: We determined the single time point concentration of timolol in plasma 1 h after application of timolol 0.5% gel-forming solution to debrided chronic wounds, providing insight as to the safety of this emerging off-label treatment. Conclusion: The topical application of timolol for chronic wounds shares the same safety profile as the widely used application of ocular administration for glaucoma.

Limb salvage of the foot with Lisfranc amputation following squamous cell carcinoma.

The indolent character of squamous cell carcinoma of the foot can be misleading and might result in unwarranted excisions or delayed treatment.

Cellular versus acellular matrix devices in the treatment of diabetic foot ulcers: Interim results of a comparative efficacy randomized controlled trial.

Healing of diabetic foot ulcers is a major challenge. Despite adhering to optimal standard of care (SOC), less than 30% of wounds heal after 20 weeks. Advanced cellular tissue-based products have shown better healing over SOC, albeit with great cost and modest improvement. We hypothesized no difference in healing effected by either cellular (Dermagraft), noncellular (Oasis) devices, relative to SOC in treating diabetic foot ulcer in a randomized controlled trial. The primary and secondary outcomes were the percentage of subjects that achieved complete wound closure by study endpoint (12 weeks of treatment) and study completion, respectively. During the 2-week screening phase with SOC, subjects with 40% change in ulcer size were excluded. After randomization, 56 patients entered an active treatment phase (8 weeks) followed by a maintenance phase (4-week SOC), with endpoint at visit 15, and 4 monthly follow-up visits. There was equal distribution of demographic data (p>.05) and no difference in initial wound characteristics (p>.05) between all groups. No differences were observed in complete wound closure by 12 and 28 weeks of treatment, nor were there any difference in percentage area reduction from treatment weeks 1 to 12 and from treatment weeks 1 to 28 between the groups. Each of the treatment arms showed statistically significant reduction in wound area from treatment weeks 1 to 28 (p<.05). This exploratory analysis suggests that the outcomes of treatment with either Dermagraft or Oasis matrix are comparable. We have completed enrollment, and the final data analysis is underway to make definitive conclusions.

Reclaiming Autologous Amputated Tissue for Limb Salvage of a Diabetic Foot Burn with Underlying Critical Limb Ischemia.

BACKGROUND: Diabetes mellitus is a worldwide pandemic that impacts more than 387 million people, with 29 million individuals affected in the United States alone. Diabetic patients have a 25% lifetime risk of developing a diabetic foot ulcer (DFU). Having a DFU is associated with a risk of recurrence approaching 70%. In addition, 1 in 6 patients with DFU will have a lower-limb amputation, with an associated increase in mortality ranging from 47% to 70%. Therefore, limb salvage is critical in patients with DFU. CASE STUDY: This article describes the case of a 70-year-old man with diabetes mellitus, end-stage renal disease, and peripheral arterial occlusive disease who presented with a 1.5% total-body-surface-area, third-degree burn to the left hallux with dry gangrene extending to the midfoot. Ankle brachial indexes were 0.66 on the left and 0.64 on the right. Toe pressures on the left were absent because of extensive dry gangrene. His right foot had a prior transmetatarsal amputation. Using a retrograde pedal approach, a chronic total occlusion of the left posterior tibial artery was recanalized with balloon angioplasty. He then underwent a transmetatarsal amputation with closure, except that the plantar medial side could not be closed without tension. Therefore, an autologous full-thickness skin graft, from the amputation specimen, was used to bridge the defect. DISCUSSION: At 32-week follow-up, the wound was healed, the graft had fully incorporated, and the patient was ambulating well using custom orthotic footwear. The creative use of amputated tissue to assist with wound coverage has not been well described in the literature.