ABSTRACT
INTRODUCTION: Patients with chronic scrotal content pain (CSCP) lack effective, non-invasive treatment options. We aimed to determine the local and systemic safety, tolerability, pharmacokinetics (PK), and efficacy of a long-lasting local anesthetic in patients with CSCP. METHODS: This was a prospective, single-center, open-label, single-arm, phase 1, dose-escalating trial completed between October 2019 and March 2021. Twelve patients ≥19 years old with unilateral scrotal pain lasting ≥3 months reporting an average maximum pain score over seven days of ≥4 on a 0-10 numerical rating scale (NRS) were included. Patients underwent a test spermatic cord block and those reporting a decrease of ≥2 points were included. The investigational drug, ST-01 (sustained-release lidocaine polymer solution), is a long-acting injection of lidocaine around the spermatic cord. Subjects were provided a NRS dairy and recorded their NRS score until day 28. The Chronic Epididymitis Symptom Index (CESI) was completed on days 0, 7, 14, and 28. All patients underwent an examination and assessment for adverse events (AE) on days 0, 1, 7, 14, and 28. Exploratory statistical hypothesis testing was planned for this study due to its investigative nature. RESULTS: There were no serious adverse events (SAEs) reported. All subjects reported at least one treatment-emergent adverse event (TEAE); 83% of related AEs were injection-site reactions consisting of swelling and bruising. NRS was reduced across all cohorts between baseline and end of study. CONCLUSIONS: This study provides evidence that the novel ST-01 treatment is safe and well-tolerated.
ABSTRACT
BACKGROUND: The primary objective of this study was to determine whether addition of the selective P-glycoprotein (P-gp) inhibitor tariquidar (XR9576) to chemotherapy could induce an objective tumor response in patients who previously were resistant to the same agents. The secondary objectives were to evaluate P-gp expression by immunohistochemistry (IHC), to determine functional activity of the P-gp transporter before and after administration of tariquidar with serial technetium-99m ((99m)Tc)-sestamibi scans, and to correlate those parameters with clinical response. METHODS: Seventeen women with Stage III-IV breast carcinoma were included in the study who progressed (n = 13 women) or had stable disease (n = 4 women) on doxorubicin-containing or taxane-containing chemotherapy regimens. During the study, the same chemotherapy was continued without dose modifications, but tariquidar (150 mg intravenously) was added to the treatment regimen. RESULTS: Thirty-six percent of patients had P-gp-positive tumors by IHC, and 5 patients (29%) experienced increases > or = 10% in sestamibi uptake (median increase, 40%; range, 10-63%) after the administration of tariquidar. There was one partial response in a patient who had the greatest increase in sestamibi uptake and who also showed inducible P-gp expression. There was one patient who experienced severe doxorubicin/docetaxel-related toxicity after tariquidar was added to her chemotherapy regimen. CONCLUSIONS: Tariquidar showed limited clinical activity to restore sensitivity to anthracycline or taxane chemotherapy. Functional imaging of the tumor with (99m)Tc-sestamibi scans before and after administration of multidrug-resistance inhibitor may be useful to identify the small subset of patients who could benefit from multidrug-resistance modulation in future trials.
