View clinical trials related to Chemoprevention.
Filter by:Seasonal malaria chemoprevention (SMC) is a highly effective community-based intervention to prevent malaria infections caused by Plasmodium falciparum in areas where the burden of malaria is high and malaria transmission is seasonal. SMC is commonly seen as a success story in the Sahel region, however, there are regions in east and southern Africa where malaria transmission is seasonal, and the burden is high. However, the same decision-making frameworks that was used in the Sahel are unlikely to be applicable to east and southern Africa due to higher pre-existing resistance to the drugs used, seasonality heterogeneity, contextual difference, and unknown cost-effectiveness, amongst others. This study aims to estimate the chemoprevention efficacy, potential upscale impact, acceptability, and feasibility of SMC with sulfadoxine-pyrimenthamine + amodiaquine (SP+AQ) medicines in Niassa Province in Mozambique. The study is divided into two separate components with different objectives which outputs feed into each other: a non-randomized controlled trial to estimate the chemoprevention efficacy of SP+AQ; and a qualitative study that will evaluate the feasibility and acceptability of the intervention. These will be the first studies analysing the chemoprevention efficacy, feasibility, acceptability, and potential scale-up impact of SMC in Niassa Province, Mozambique The outcomes of these studies aim to guide future policy changes at local, national, and international levels and potentially allow for a historically successful program to expand in a sustained and cost-effective way beyond the Sahel region.
Most of the sporadic colorectal cancer (CRC )develop from colorectal adenoma (CRA), patients with CRA have a high risk of recurrence and development of metachronous CRA or CRC after removal, therefore, the investigators conducted this clinical trial to explore the chemoprevetion effect of metformin for CRA recurrence after removal.
African American (AA) women with breast cancer (BC) have higher mortality and are associated with worse outcomes when treated with available adjuvant treatments. Addressing this survival disparity will depend on identifying contributing biologic factors that can be translated into new treatments. Preclinical studies have shown that Insulin-like growth factor-II (IGF-II)expression was significantly higher in AA cell lines and tissue samples when compared to Caucasians indicating that IGF-II is an important biologic factor contributing to higher breast cancer mortality in AA women and is also responsible for chemoresistance in BC cells. In addition preclinical studies also demonstrated that resveratrol (RSV) inhibits IGF-II and induces apoptosis in BC cell lines. Researchers want to test IGF-II levels at baseline in healthy African American women and monitor levels while on resveratrol therapy for 6 weeks.
Primary sclerosing cholangitis (PSC) is a chronic inflammatory condition of the bile ducts of unknown etiology. It is characterized by diffuse inflammation and stricturing of the entire biliary tree, eventually resulting in cirrhosis of the liver. Patients with PSC are at increased risk for the development of cholangiocarcinoma (CCA), a cancer arising from bile duct epithelium. This risk is estimated to be approximately 1 to 1.5% per year. It is postulated that chronic inflammatory changes in the biliary epithelium promote CCA formation. The prognosis of CCA is fatal. The only potentially curative therapy is surgical; however, only a minority of patients qualify for surgical treatment. Several studies have demonstrated overexpression of the epidermal growth factor receptor (EGFR) in CCA cells. EGFR is a type 1 tyrosine kinase promoting cell proliferation, migration and altered cell adhesion - typical characteristics of malignant neoplasias. In CCA cells, EGFR-activation is sustained resulting in cancer progression. In human CCA samples, EGFR-expression correlates with higher histologic grade, poor prognosis, and risk of recurrence. The EGFR gene is located on the short arm of chromosome 7 (7p12). Chromosomal abnormalities of the bile duct epithelium, particularly trisomy 7 (i.e. three copies of chromosome 7) can be detected in biliary epithelial samples obtained by endoscopic retrograde cholangiopancreatography (ERCP) in PSC patients. The finding of cells with trisomy 7 has preceded the development of aneuploidy and multiple chromosomal abnormalities in a number of patients, the latter chromosomal abnormalities are characteristic of CCA. Trisomy 7 amplifies the gene for EGFR thereby presumably promoting overexpression of this growth factor receptor. In a cohort of patients with Trisomy 7 and Primary Sclerosing Cholangitis patients followed for 1 year, the rate of development of Cholangiocarcinoma was 35% (n=37, Dr. Gores, unpublished observation). Patients without cytologic abnormalities were at minimal risk for the development of CCA. Erlotinib (Tarceva) is a human EGFR type 1 tyrosine kinase inhibitor. Tarceva received FDA approval as single agent treatment for patients with locally advanced or metastatic non-small cell lung cancer. In a randomized, double blind, placebo controlled trial of 731 patients, receiving 150 mg of Tarceva or placebo once daily, median survival was prolonged to 6.7 months from 4.7 months (p<0.001). Analysis of epidermal growth factor receptor expression (45% of total study patients) demonstrated greater survival benefit in EGFR positive patients. Tarceva in combination with Gemcitabine is also FDA approved as first line therapy in patients with locally advanced, unresectable or metastatic pancreatic cancer. Our central hypothesis is that patients with trisomy 7 will have carcinogenic changes including EGFR overexpression. EGFR blockade will inhibit a growth/survival advantage for these premalignant clones eliminating them from the biliary epithelium. As an initial step towards testing this hypothesis, the tolerability of Tarceva in this patient population needs to be established. This study will assist in determining the safety and tolerability of Tarceva in patients with primary sclerosing cholangitis. This study will be followed by a Phase 2 randomized controlled trial of Tarceva in patients with Primary Sclerosing Cholangitis with Trisomy 7.