A phase I trial of the bombesin/gastrin-releasing peptide (BN/GRP) antagonist RC3095 in patients with advanced solid malignancies

Summary Bombesin/gastrin-releasing peptides (BN/GRP) were shown to bind selectively to cell surface receptors, stimulating the growth of various types of malignancies in murine and human models. The novel BN/GRP synthetic receptor antagonist, RC-3095, was able to produce long-lasting tumor regressions in murine and human tumor models in vitro and in vivo. Animal toxicology studies showed no detectable organ toxicity apart from local irritation at the injection site. The purpose of this study was to determine the safety and feasibility of the administration of RC-3095 by daily subcutaneous injections in patients with advanced and refractory solid malignancies. Twenty-five patients received RC-3095 once or twice-daily at doses ranging from 8 to 96 ug/kg. Dose was escalated in groups of 3–5 patients per dose level. The only toxicity observed was local discomfort in the injection site at the highest doses. A single dose administration of RC-3095 at the highest dose level (96 ug/kg) was tested in a clearly hypergastrinemic individual with the Zollingen-Ellison syndrome and produced a decrease in plasma gastrin down to 50% of basal levels in 6 h. There was no objective tumor responses in patients included in the study. A short-lasting minor tumor response was observed in a patient with a GRP-expressing progressive medullary carcinoma of the thyroid. Due to problems with the analytical method, plasma pharmacokinetic data was obtained only from two patients included at the highest dose level. In these patients, RC-3095 reached plasma concentrations >100 ng/mL for about 8 h, which were within therapeutic levels on the basis of prior data obtained in mice and rats. The plasma elimination half-life was between 8.6–10.9 h. Due to the occurrence of local toxicity at the injection site, the dose escalation procedure could not be fully evaluated up to a maximum tolerated dose. Thus, a recommended dose of RC-3095 for Phase II trials could not be clearly established. Considering the novelty of its mechanism of action and impressive preclinical anti-tumor activity, further studies exploiting new formulations of RC-3095 for human use, such as slow-release preparations, and analogues with a more favorable pharmacokinetics are warranted.     

Bioequivalence study of two enalapril maleate tablet formulations in healthy male volunteers Pharmacokinetic versus pharmacodynamic approach

Objective: Two different conventional release enalapril maleate tablet formulations were evaluated for their relative bioavailability (Eupressin tablets 10 mg, Biosintética as the test formulation vs Renitec tablets 10 mg Merck Sharp & Dhome, as the reference formulation). A single 20 mg oral dose of each preparation was administered to 18 healthy male adult volunteers and their bioequivalence was assessed by comparing the serum enalaprilat and total enalapril (enalaprilat plus enalapril maleate) concentration-time curves. Angiotensin converting enzyme (ACE) activity was also quantified in each serum sample. Results: The pharmacokinetic parameters obtained for each formulation were the area under the time-concentration curve from 0 to 24 h (AUC_[0–24]), maximum concentration C_max and the time at which it occurred (t_max). When serum enalaprilat concentration-time curves were employed to assess bioequivalence, the formulations were bioequivalent in the extent but not in the rate of absorption. However, no difference in either the extent or the rate of absorption were observed when serum total enalapril vs time curves were analysed. ACE activity-time curves were similar for both formulations and showed that ACE was 90% inhibited 3–5 h after enalapril administration, and till approximately 50% after 24 h. At that time, circulating enalaprilat and total enalapril levels were less than the tenth of C_max. Conclusion: The results show that complete bioequivalence of the two formulations can be concluded from serum total enalapril concentration data, and that serum ACE activity is not a suitable pharmacodynamic variable for assessing bioequivalence. Received: 29 May 1995/Accepted in revised form: 30 October 1995     

Comparative bioavailability of two ramipril formulations after single-dose administration in healthy volunteers

OBJECTIVE: To assess the bioequivalence of a ramipril 5 mg tablet formulation (ramipril test formulation from Laboratórios Biosintética Ltda (Sao Paulo, Brazil) and Triatec from Aventis Pharma (Sueano, Brazil) standard reference formulation) in 26 healthy volunteers of both sexes. METHODS: The study was conducted using an open, randomized, 2-period crossover design with a 2-week washout interval. Plasma samples were obtained over a 36-hour period. Plasma ramipril and ramiprilat concentrations were analyzed by liquid chromatography coupled to tandem mass spectrometry (LC-MS-MS) with positive ion electrospray ionization using multiple reaction monitoring (MRM). From the ramipril and ramiprilat plasma concentration vs. time curves, the following pharmacokinetic parameters were obtained: AUClast, AUCinf and Cmax. RESULTS: The limit of quantification was 0.2 ng x ml(-1) and 1.0 ng x ml(-1) for ramipril and ramiprilat, respectively. The geometric means and 90% confidence intervals (CI) for Ramipril/Triatec and Ramiprilat/Triatec percent ratios were: 104.69% (90% CI = 93.21-117.59%) for Cmax, 102.49% (90% CI = 92.76-113.24%) for AUClast, 103.60% (90% CI = 93.56 114.73%) for AUCinf, 108.48% (90% CI = 98.86-119.03%) for Cmax, 105.88% (90% CI = 101.55-110.39%) for AUClast, 97.30% (90% CI = 90.17-104.99%) for AUCinf, respectively. CONCLUSION: Since the 90% CI for AUClast, AUCinf and Cmax ratios were within the 80-125% interval proposed by the U.S. FDA, it was concluded that the ramipril formulation produced by Laboratórios Biosintética Ltda is bioequivalent to the Triatec formulation in both rate and extent of absorption.     

Autologous conjunctival epithelium transplantation and scleral patch graft for postlensectomy wound leakage in Marfan syndrome

Purpose. We report a case of woman with Marfan syndrome and longstanding postlensectomy scleral wound dehiscence. Methods. A 34-year-old woman with Marfan syndrome who underwent lensectomy 20 years ago had conjunctival leakage with chronic hypotony and conjunctival cystic degeneration secondary to scleral wound dehiscence. Presentation, clinical evaluation, and particular treatment with autologous cultivated conjunctival epithelium transplantation and scleral patch graft are described. Results. A 6-month follow-up confirmed complete epithelization of the ocular surface and absence of leaking from the wound with normal intraocular pressure. Conclusions. Transplantation of autologous cultivated conjunctival epithelium appears to be a valid strategy in the treatment of ocular disease requiring extensive excision of the conjunctiva.     

A randomized double-blind,non-inferiority Phase II trial,comparing dapaconazole tosylate 2% cream with ketoconazole 2% cream in the treatment of Pityriasis versicolor

Objectives: The objective of this research was to evaluate the efficacy of a new antifungal imidazole, dapaconazole tosylate, in the treatment of Pityriasis versicolor (PV).

Design and methods: Sixty patients with clinical and mycological diagnosis of PV were randomly assigned to receive either 1 g dapaconazole tosylate 2% cream or 1 g ketoconazole 2% cream. Treatments were applied once a day for 28 days. A dermatologist evaluated efficacy and safety daily, and weekly laboratorial tests were performed. The primary end point was a clinical and mycological cure of lesions after 28 days of treatment. The secondary end point was the time to clinical healing assessed by Kaplan–Meier analysis and Log-rank testing.

Results: Fifty-three patients adhered to protocol rules. Clinical and mycological cure was achieved in 84.6% (22/26) and 92.6% (25/27) of patients treated with ketoconazole and dapaconazole, respectively (difference [effect size] = 8.0%, Standard error of difference: 8.69%, 95% CI: –6.3 to 22.3%). Median time to healing was 23.5 and 21 days for ketoconazole and dapaconazole, respectively (p = 0.126). Adverse events occurred only in ketoconazole-treated patients (13%; 4/30).

Conclusion: Dapaconazole tosylate is non-inferior to ketoconazole when used at a dose of 20 mg/day for 28 consecutive days for the treatment of PV. Dapaconazole also demonstrated a good safety profile.     

Normal exophthalmometric values in children

We used a Hertel exophthalmometer to measure the degree of ocular protrusion in 852 subjects who had no history of orbital trauma or disease, endocrine disease, severe myopia, buphthalmos, or craniofacial deformities. The subjects ranged in age from 3 to 10 years. No statistically significant difference was observed between boys and girls or between right and left eyes in each age group. The mean normal protrusion values ranged from 9.11 mm in the 3-year-old group to 11.67 mm in the 10-year-old group. The mean outer orbital margin distance ranged from 78.7 mm in the 3-year-old group to 89.1 mm in the 10-year-old group. The data obtained were tabulated to plot percentile distribution curves of normal exophthalmometric values and outer orbital margin distance in children. No subject had more than 2 mm of asymmetry between the eyes.     

Isolated lesion of the axillary nerve: surgical treatment and outcome in 12 cases

We report a series of 12 cases of isolated lesions of the axillary nerve treated surgically. We discuss the pathogenesis, clinical pattern, and surgical treatment of this lesion together with the results obtained.     

Distinction between endometrial and endocervical adenocarcinoma: an immunohistochemical study.

We investigated the possibility of distinguishing between primary endometrial and endocervical adenocarcinomas by using a panel of immunohistochemical stains, which included vimentin (VIM), carcinoembryonic antigen (CEA), epithelial membrane antigen (EMA), and cytokeratins 7 and 20 (CK7 and CK20). Twenty-nine endocervical adenocarcinomas (CCAs) and 30 endometrial adenocarcinomas (EMCAs) including cases with overlapping histologic features (CCAs with endometrioid differentiation [15/29] and EMCAs with mucinous differentiation [16/30]) were evaluated. Most EMCAs (29/30, 97%) were VIM positive, whereas only 2/29 (7%) CCAs were VIM positive. The great majority of EMCAs (28/30) and all 29 CCAs were CK7 positive, whereas all 30 EMCAs and 27/29 CCAs were negative for CK20. CEA positivity was more common in CCAs (18/29, 62%) than in EMCAs (8/30, 27%). EMA positivity was present in all 30 EMCAs and in 26 of 29 (90%) CCAs. We conclude that VIM and CEA are useful immunohistochemical markers in distinguishing EMCAs and CCAs, but CK7, CK20, and EMA are not useful in this distinction.