Michael H. Silverman

ZYC101a for treatment of high-grade cervical intraepithelial neoplasia: a randomized controlled trial.

OBJECTIVE: The objective of this study was to assess the safety and efficacy of a novel therapeutic, ZYC101a, for the treatment of women with histologically confirmed cervical intraepithelial neoplasia (CIN) 2/3. ZYC101a contains plasmid-DNA–encoding fragments derived from the E6 and E7 proteins of human papillomavirus (HPV) 16 and 18, and is formulated within small biodegradable microparticles. METHODS: A multicenter, double-blind, randomized, placebo-controlled trial was conducted in a group of women with biopsy-confirmed CIN 2/3. Subjects were randomized to 3 intramuscular doses of either placebo or ZYC101a (100 or 200 μg). Six months after the first injection, subjects underwent cervical conization. The primary endpoint for this study was histologically confirmed resolution of CIN 2/3. A total of 161 subjects were randomized, dosed, and evaluated for safety. After central pathology review, 127 subjects were evaluable for efficacy. RESULTS: The most common adverse events were related to the injection site, were mild to moderate, and did not worsen at later treatments. The proportion of subjects who resolved was higher in the ZYC101a groups compared to placebo (43% versus 27%), but the difference was not statistically significant (P = .12). In a prospectively defined population of women younger than 25 years (n = 43), resolution was significantly higher in the combined ZYC101a groups compared to placebo (70% versus 23%; P = .007). ZYC101a activity was not restricted to HPV-16– or HPV-18–positive lesions. CONCLUSIONS: ZYC101a was shown to be well tolerated in all patients and to promote the resolution of CIN 2/3 in women younger than 25 years. LEVEL OF EVIDENCE: I

A Phase 2, randomized, double-blind, placebo-controlled trial of clinical activity and safety of subcutaneous A6 in women with asymptomatic CA125 progression after first-line chemotherapy of epithelial ovarian cancer

OBJECTIVES A6 is a novel peptide that interferes with single-chain urokinase plasminogen activator activity and has shown anti-angiogenic, anti-migratory, and anti-invasive properties. We evaluated clinical efficacy and safety of subcutaneously administered A6 in women with epithelial ovarian cancer. METHODS Women with epithelial ovarian, fallopian tube, or primary peritoneal cancer in clinical remission after first-line chemotherapy with 2 consecutive increases of CA125 values above normal but with no disease on physical examination or imaging studies were randomly assigned to receive daily subcutaneous injections of placebo, low-dose A6 (150 mg), or high-dose A6 (300 mg) until disease progression or end of study participation. Primary endpoints were time to clinical progression of disease and safety of A6. Secondary endpoints were changes in serum CA125 and biomarkers of the urokinase system. RESULTS Data are available for 24 women (placebo, n=12; low-dose, n=8; high-dose n=4). A6 therapy was associated with a statistically significant delay in time to clinical progression (log-rank p-value 0.01) with a median of 100 days (95% CI: 64,168) for women who received A6 compared with 49 days (95% CI: 29,67) for women who received placebo. The treatments appeared to be well tolerated. Treatment was not associated with CA125 response (p=0.44). On-treatment values for plasma urokinase plasminogen activator receptor were statistically significantly lower in the A6 groups compared with placebo (p=0.02). CONCLUSIONS A6 therapy increases time to clinical disease progression and appears to be well tolerated in this patient population.

Continuous safety monitoring for randomized controlled clinical trials with blinded treatment information Part 1: Ethical considerations

The protection of patient safety is the principal responsibility of clinical trial investigators, and must be assured even if that were to prevent successful completion of a trial. Yet, the decision to prematurely stop a blinded, randomized controlled clinical trial can be extremely complicated, involving a tangle of ethical, statistical, and practical issues. Questions are quickly answered when conclusive evidence of harm has been established for trial participants, or when the potential for harm exceeds an acceptable limit of comfort for an oversight body. Less readily addressed are those situations in which early alarms warn of possible harm, but the data are too preliminary or incomplete to reach a satisfactory decision as to whether or not to stop the study. Early study termination without sufficient evidence disallows the study question from being answered and may allow an inferior treatment to remain in use, or prevent a superior one from being discovered. Even without early stopping, as a study proceeds, worrisome trends may lead to overzealous (or overly cautious) looks at study data which could jeopardize the integrity of the findings. Trial investigators and safety monitoring groups, aided by objective statistical rules and thoughtful deliberations, share responsibility for patient welfare. Statistical guidelines must not frustrate ethical concerns, but, rather, should be designed to promote the highest ethical and scientific outcomes possible, safeguarding both trial participants and the public - the ultimate beneficiaries of clinical trials.

Abstract A89: A phase I study of the novel DNA topoisomerase-1 inhibitor, TLC388 (Lipotecan®), administered intravenously to patients with advanced solid tumors.

Introduction: TLC388 (Lipotecan) is a potent Topoisomerase-1 inhibitor and it can disrupt both Sonic Hedgehog and HIF1-α pathways to overcome cancer drug resistance and inhibit angiogenesis induced by tumor hypoxia. This phase I first-in-human study of Lipotecan examined the MTD, safety, anti-tumor activity and pharmacokinetic profiles of TLC388 in patients with advanced incurable solid tumors. Methods: Lipotecan was administered intravenously on day 1, 8 and 15 of a 28-day cycle. Patients underwent safety assessments regularly and tumor assessments every other cycle. Pharmacokinetic samples were drawn on days 1, 8 and 15 of cycles 1 and 2 for all treated patients. Results: The enrollment for this study has been concluded and 54 previously-treated patients with advanced or metastatic solid tumors received Lipotecan. The dose was escalated from 1.5 mg/m2 to 60 mg/m2 over 12 patient cohorts (11 dose levels). MTD was reached at 50 mg/m2, following the emergence of two DLTs at 60 mg/m2: one grade 3 febrile neutropenia and one toxicity that precluded treatment within the 14 days specified by the protocol. Other DLTs occurred in other dose levels include hyponatremia (grade 3 and 4; 40 mg/m2) and thrombocytopenia (grade 4; 40 mg/m2). To date, all the subjects except one have completed the study. Lipotecan given at this dosing schedule was well-tolerated and no cumulative toxicity was observed. Non-hematological toxicity was generally mild, including fatigue (41%), nausea (37%), diarrhea (28%), vomiting (14%) and constipation (14%). Anemia was the most frequently reported hematological toxicity (67.0%). Neutropenia (30%), thrombocytopenia (28%), and leukopenia (26%) were also reported. Grade 3 or grade 4 hematological toxicity included neutropenia (28%), anemia (22%), leucopenia (17%), and thrombocytopenia (13%). Other G3/4 non-hematological side effects included hyponatremia (11%), abdominal pain (7%), fatigue (6%), and hypokalaemia (6%). Twenty one of 35 evaluable patients (60%) continued therapy beyond cycle 2, received a median of 5 cycles (range of 2–18 cycles), and experienced stable disease or minor tumor regression. Prolonged (≥ 6 months) stable disease was noted in 9 patients (26%), including renal (chromophobe and clear cell types), docetaxel refractory prostate, salivary gland, sorafenib refractory hepatic, and vaginal cancers. One minor response occurred in a heavily pretreated 70-year-old male with stage II B thymoma cancer metastatic to lung, liver and lymph nodes who was treated for 18 courses and remains on the study. PET-CT scan revealed reduction in his tumor size by 27% at the end of cycle 16. His disease had progressed through prior treatment with cyclophosphamide, cisplatin and doxorubicin. Pharmacokinetics of TLC388 were dose-independent; mean (SD) values for the volume of distribution at steady-state and clearance were 857 (1122) L/m2 for S,R-TLC388 and 996 (1333) L/m2 for S,S-TLC388, and 7420 (8151) L/h-m2 for S,R-TLC388 and 4949 (5678) L/h-m2 for S,S-TLC388, respectively. The half-life values averaged 0.76 (1.15) hours for S,R-TLC388 and 0.75 (1.13) hours for S,S-TLC388. Conclusions: Lipotecan administered doses up to 50 mg/m2 on current treatment schedule is safe, well tolerated, and demonstrates broad antitumor activity to support Phase 2 disease-specific investigations. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr A89.

A phase I clinical trial of dTCApFs, a derivative of a novel human hormone peptide, for the treatment of advanced/metastatic solid tumors

The aim of the present phase I first-in-human study was to investigate the safety/efficacy of dTCApFs (a novel hormone peptide that enters cells through the T1/ST2 receptor), in advanced/metastatic solid tumors. The primary objective of this open-label dose-escalation study was to determine the safety profile of dTCApFs. The study enrolled patients (aged ≥18 years) with pathologically confirmed locally advanced/metastatic solid malignancies, who experienced treatment failure or were unable to tolerate previous standard therapy. The study included 17 patients (64% male; median age, 65 years; 47% colorectal cancer, 29% pancreatic cancer). The patients received 1–3 cycles of escalating dTCApFs doses (6–96 mg/m2). The mean number ± standard deviation of treatment cycles/patient was 3.2±1.4; no dose-limiting toxicities were observed up to a dose of 96 mg/m2, and the maximum tolerated dose was not reached. Half-life, maximal plasma concentration, and dTCApFs exposure were found to be linearly correlated with dose. Five patients were treated for ≥3 months (12, 24, 48 mg/m2) and experienced stable disease throughout the treatment period, and 1 experienced pathological complete response. Analysis of serum biomarkers revealed decreased levels of angiogenic factors at dTCApFs concentrations of 12–48 mg/m2, increased levels of anticancer cytokines, and induction of the endoplasmic reticulum (ER) stress biomarker GRP78/BiP. Efficacy and biomarker data suggest that patients whose tumors were T1/ST2-positive exhibited a better response to dTCApFs. In conclusion, dTCApFs was found to be safe/well-tolerated, and potentially efficacious, with linear pharmacokinetics. Consistent with preclinical studies, the mechanism through which dTCApFs exerts anticancer effects appears to involve induction of ER stress, suppression of angiogenesis, and activation of the innate immune response. However, further studies are warranted.

Inhibition of IL-17 and IL-23 in Human Keratinocytes by the A3 Adenosine Receptor Agonist Piclidenoson

Interleukin-17 and interleukin-23 play major roles in the inflammatory process in psoriasis. The Gi protein-associated A3 adenosine receptor (A3AR) is known to be overexpressed in inflammatory cells and in peripheral blood mononuclear cells (PBMCs) of patients with autoimmune inflammatory conditions. Piclidenoson, a selective agonist at the A3AR, induces robust anti-inflammatory effect in psoriasis patients. In this study, we aimed to explore A3AR expression levels in psoriasis patients and its role in mediating the anti-inflammatory effect of piclidenoson in human keratinocyte cells. A3AR expression levels were evaluated in skin tissue and PBMCs derived from psoriasis patients and healthy subjects. Proliferation assay and the expression of signaling proteins were used to evaluate piclidenoson effect on human keratinocytes (HaCat). High A3AR expression levels were found in a skin biopsy and in PBMCs from psoriasis patients in comparison to healthy subjects. Piclidenoson inhibited the proliferation of HaCat cells through deregulation of the NF-κB signaling pathway, leading to a decrease in interleukin-17 and interleukin-23 expression levels. This effect was counteracted by the specific antagonist MRS 1523. A3AR overexpression in skin and PBMCs of psoriasis patients may be used as a target to inhibit pathological cell proliferation and the production of interleukin-17 and interleukin-23.