Individual responses to a single oral dose of albendazole indicate reduced efficacy against soil-transmitted helminths in an area with high drug pressure

BACKGROUND

Albendazole (ALB) is administered annually to millions of children through global deworming programs targeting soil-transmitted helminths (STHs: Ascaris lumbricoides, Trichuris trichiura and hookworms, Necator americanus and Ancylostoma duodenale). However, due to the lack of large individual patient datasets collected using standardized protocols and the application of population-based statistical methods, little is known about factors that may affect individual responses to treatment.

METHODOLOGY/PRINCIPAL FINDINGS

We re-analyzed 645 individual patient data from three standardized clinical trials designed to assess the efficacy of a single 400 mg oral dose of ALB against STHs in schoolchildren from different study sites, each with varying history of drug pressure based on duration of mass drug administration programs: Ethiopia, low; Lao People's Democratic Republic (PDR), moderate; Pemba Island (Tanzania), high. Using a Bayesian statistical modelling approach to estimate individual responses (individual egg reduction rates, ERRi), we found that efficacy was lower in Pemba Island, particularly for T. trichiura. For this STH, the proportion of participants with a satisfactory response (ERRi ≥50%), was 65% in Ethiopia, 61% in Lao PDR but only 29% in Pemba Island. There was a significant correlation between ERRi and infection intensity prior to drug administration (ERRi decreasing as a function of increasing infection intensity). Individual age and sex also affected the drug response, but these were of negligible clinical significance and not consistent across STHs and study sites.

CONCLUSIONS/SIGNIFICANCE

We found decreased efficacy of ALB against all the STHs analyzed in Pemba Island (Tanzania), an area with high drug pressure. This does not indicate causality, as this association may also be partially explained by differences in infection intensity prior to drug administration. Notwithstanding, our results indicate that without alternative treatment regimens, program targets will not be achievable on Pemba Island because of inadequate efficacy of ALB.

TRIAL REGISTRATION

The study was registered on Clinicaltrials.gov (ID: NCT03465488) on March 7, 2018.

Leishmania braziliensis amastigotes stimulate production of IL-1β, IL-6, IL-10 and TGF-β by peripheral blood mononuclear cells from nonendemic area healthy residents

Leishmania (Viannia) braziliensis causes cutaneous and mucosal leishmaniasis in several countries in Latin America. In mammals, the parasites live as amastigotes, interacting with host immune cells and stimulating cytokine production that will drive the type of the specific immune responses. Generation of Th17 lymphocytes is associated with tissue destruction and depends on IL-1β, IL-6, TGF-β and IL-23 production, whereas IL-10 and TGF-β are associated with tissue protection. Here, we evaluate whether amastigotes stimulate peripheral blood mononuclear cells (PBMCs) from healthy donors to produce the major cytokines responsible for the generation of Th17. Seven L. (V.) braziliensis isolates from patients with different clinical forms of leishmaniasis were expanded in interferon-γ knockout mice to obtain amastigotes and in culture to get promastigotes. The parasites were used to stimulate PBMCs from healthy donors, and cytokine production was evaluated by ELISA or qPCR. Amastigotes and promastigotes induced IL-10 production in PBMCs; however, only amastigotes induced IL-1β, IL-6 and TGF-β. These data demonstrate for the first time that L. (V.) braziliensis amastigotes directly stimulate production of a unique pattern of cytokines that could contribute to the generation of Th17.

Abstract P4-11-03: Effect of tamoxifen and raloxifene on proliferative activity of breast epithelium in premenopausal women

Background: Both Tamoxifen and raloxifene have been demonstrated to be effective to reduce the incidence of breast cancer among women. Objective: To compare the effects of raloxifene (60 mg/day) and tamoxifen (20 mg/day) on the proliferative activity of normal human breast epithelium, during the luteal phase of the menstrual cycle, by means of the immunoexpression of Ki-67/MIB-1. Patients and Methods: Forty-eight women presenting benign breast nodules with an indication for lesion excision took part in this study. These women were randomized to use tamoxifen or raloxifene for 22 days. They underwent surgery after using the medication, and a one-centimeter fragment of normal breast tissue was removed to study the immunoexpression of Ki-67. For this, the frequency of cells immunolabeled for Ki-67/MIB-1 per thousand epithelial cells was quantified. Results: The mean percentage ratios between immunolabeled and non-labeled cells were 2.02 (±1.09) and 3.13 (±3.23) for the tamoxifen and raloxifene groups, respectively. There was no statistically significant difference between the two groups, tamoxifen (n = 16) and raloxifene (n = 14), in relation to the immunoexpression of Ki-67 (p = 0.205). The mean of progesterone level was 19.62 (±17.67) for the tamoxifen group and 14.59 (±8.98) for the raloxefene group (p = 0.32). The plasma levels of estradiol, the values found were: 355.72 (± 337.98) and 171.02 (± 119.83) for groups of tamoxifen e raloxifene groups, respectively (p = 0.055). Conclusion: In this study, we observed that there was no difference in the potential for reducing the proliferative activity of normal breast epithelium between tamoxifen and raloxifene in premenopausal women.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-11-03.

Investigation of human papillomavirus by hybrid capture II in cervical carcinomas including 113 adenocarcinomas and related lesions

Hybrid capture is an easy and highly sensitive technique for screening population due to its capacity to detect malignant and premalignant lesions of the cervix. To evaluate its sensitivity, we investigated the frequency of high-risk human papillomavirus (HPV) infection and its correlation with glandular malignant lesions, analyzing a total of 113 cases of adenocarcinomas and related lesions. High-risk HPV was investigated using a hybrid capture II (HC2) assay. Samples were collected in two different ways: either brushed directly from surgical specimens before fixation or collected from the patients. We also investigated the frequency of HPV in squamous malignant lesions, 65 squamous cell carcinomas (SCC) and 66 in situ squamous cell carcinomas (ISSCC), to compare the occurrence of HPV for these lesions. The 113 glandular lesions comprised 62 invasive adenocarcinomas (IAC), 8 in situ adenocarcinomas (ISAC), 26 IAC plus SCC, and 17 adenosquamous cells carcinomas (ASCC). The HPV-positive reactions were as follows: 51 (82.2%) in IAC, 8 (100%) in ISAC, 25 (96.1%) in IAC plus SCC, and 14 (82.3%) in ASCC. HC2-positive results in the squamous malignant lesions were as follows: 58 of 63 (89.0%) for SCC and 94 of 103 (91.2%) for ISSCC. High-risk HPV infection was quite similar for glandular and pure squamous invasive malignant lesions, 82.2% and 89.0%, respectively, indicating that high-risk HPV is also highly prevalent in glandular lesions. Although hybrid capture proved to be an excellent adjunctive technique, we do not believe its results merit replacing the Pap smear as a screening tool.