A Phase I Clinical Trial to Assess Safety and Tolerability of Injectable Collagenase in Women with Symptomatic Uterine Fibroids.

Uterine fibroids feature excessive deposition of types I and III collagen. Previous ex vivo studies showed an FDA-approved collagenase (EN3835)-digested types I and III collagen fibers in fibroid tissues; however, collagenase had not been evaluated in vivo for effects on uterine fibroids. The objective was to assess the safety and tolerability of collagenase injection directly into uterine fibroids. This was a prospective, open label, dose escalation study. The study participants were fifteen women aged 35-50 years with symptomatic uterine fibroids planning to undergo hysterectomy. Three subjects received saline and methylene blue, three subjects received a fixed dose of EN3835, and 9 subjects received stepped, increasing dosages of EN3835, all by transvaginal, ultrasound-guided injections. Primary outcome measures were safety and tolerability of the injection and change in collagen content between treated and control tissues. There were no significant adverse events following injection of EN3835 into uterine fibroids. Masson's trichrome stains revealed a 39% reduction in collagen content in treated samples compared to controls (p <0.05). Second harmonic generation (SHG) analysis showed treated samples to have a 21% reduction in density of collagen compared to controls. Picrosirius-stained collagenase-treated fibroids showed collagen fibers to be shorter and less dense compared to controls. Subjects reported a decrease in fibroid-related pain on the McGill Pain Questionnaire after study drug injection in Group 2 at both 4-8 days and 60-90 days post-injection. The findings indicated that injection of collagenase was safe and well tolerated. These results support further clinical investigation of collagenase as a minimally invasive treatment of uterine fibroids. NCT0289848.

Randomized controlled trial of sildenafil for preventing recurrent ischemic priapism in sickle cell disease.

BACKGROUND: Successful preventive therapy for ischemic priapism, a disorder of penile erection with major physical and psychologic consequences, is limited. We conducted a randomized, double-blind, placebo-controlled clinical trial to assess the efficacy and safety of sildenafil by a systematic dosing protocol to prevent recurrent ischemic priapism associated with sickle cell disease. METHODS: Thirteen patients with sickle cell disease reporting priapism recurrences at least twice weekly were randomized to receive sildenafil 50 mg or placebo daily, unassociated with sleep or sexual activity, for 8 weeks, followed by open-label use of this sildenafil regimen for an additional 8 weeks. RESULTS: Priapism frequency reduction by 50% did not differ between sildenafil and placebo groups by intention-to-treat or per protocol analyses (P = 1.0). However, during open-label assessment, 5 of 8 patients (62.5%) by intention-to-treat analysis and 2 of 3 patients (66.7%) by per protocol analysis met this primary efficacy outcome. No significant differences were found between study groups in rates of adverse effects, although major priapism episodes were decreased 4-fold in patients monitored "on-treatment." CONCLUSIONS: Sildenafil use by systematic dosing may offer a strategy to prevent recurrent ischemic priapism in patients with sickle cell disease.

Intravesical gemcitabine therapy for superficial transitional cell carcinoma of the bladder: a phase I and pharmacokinetic study.

PURPOSE: To determine maximum-tolerated dose, toxicities, and pharmacokinetics associated with weekly intravesical gemcitabine therapy in patients with superficial bladder cancer. PATIENTS AND METHODS: Fifteen patients with recurrent superficial transitional cell bladder carcinoma who experienced prior intravesical therapy failure were studied. Two to 4 weeks after complete transurethral resection, gemcitabine was administered intravesically, once weekly for 6 consecutive weeks. Dwell time was 2 hours. Pharmacokinetics of gemcitabine and its metabolite, 2'2'-difluorodeoxyuridine (dFdU), were studied in plasma and urine. Cystoscopy was repeated 6 weeks after therapy. RESULTS: Three-patient cohorts were enrolled sequentially at doses of 500, 1,000, and 1,500 mg in 100 mL 0.9% NaCl. Two patients received 2,000 mg in 100 mL. An additional four patients received 2,000 mg in 50 mL. No grade 4 toxicity or clinically relevant myelosuppression was noted. Nine of 13 evaluable patients were recurrence-free at 12 weeks. Low concentrations of gemcitabine (< or = 1 microg/mL) were present transiently in plasma of all patients receiving 2,000 mg in 50 mL. Gemcitabine was undetectable in plasma of other patients. dFdU was undetectable in plasma of patients receiving less than 1,500 mg. At doses > or = 1,500 mg, dFdU concentrations increased until 90 to 120 minutes and then declined little, if any. Plasma dFdU concentrations implied absorption of 0.5% to 5.5% of instilled dose. Between 61% and 100% of the gemcitabine dose was accounted for in voided urine. No dFdU was measured in voided urine. CONCLUSION: Intravesical gemcitabine, at doses up to 2 g/wk, is well tolerated, is associated with minimal systemic absorption, and has promising efficacy in treatment of superficial bladder cancer.