Clinical Trial
MP Biomedicals initiates U.S. clinical trials for HTLV Blot 2.4 confirmatory test. MP Biomedicals, LLC announced November 16 that the company has begun a clinical trial for the U.S. regulatory approval of MP Diagnostics™ HTLV Blot 2.4 for use in testing in the transfusion and transplantation community. The company has initiated the clinical data collection phase of the trial, to be completed within four to six weeks. The HTLV Blot 2.4 trial is the first of two U.S. clinical trials the company is sponsoring, Subsequent to the completion of the blot trial, the company will initiate the second trial for the MP Diagnostics™ HTLV-I/II ELISA 4.1 System, slated for early this year.
Data from the Red Cross suggest that of more than seven million donors, some 65 percent of repeatedly reactive samples will not repeat with a second screening assay of a different type. And since there are no FDA-approved confirmatory tests available in the U.S., that is, as Marek J. Nowicki, PhD, scientific director at the Mendez National Institute of Transplantation, Los Angeles, points out, a recipe for “loss of donors and unnecessary anxiety among those who tested positive using the EIA test only.” Thus there is much interest in the transplant community in the upcoming clinical trials.
New Studies
Many false positives found in available tuberculosis diagnostic tests. In populations with a low prevalence of tuberculosis (TB), the majority of positives with the three tests commercially available in the U.S for the diagnosis of TB are false positives, according to a new study. The findings were published online ahead of print publication in the American Thoracic Society's American Journal of Respiratory and Critical Care Medicine.
The cross-sectional study involved 2,017 military recruits at Fort Jackson, South Carolina, who completed a risk factor questionnaire and underwent testing with the three tests: 1) tuberculin skin test (TST); 2) the interferon gamma release assays (IGRAs) QuantiFERON®-TB Gold In-Tube test (QFT-GIT); and 3) the TSPOT® TB test (T-Spot). The specificities of TST, QFT-GIT, and T-Spot were not significantly different.
There were some limitations to the study, including the lack of a gold standard for determining the presence of M. tuberculosis infection and administrative restrictions that resulted in an increased proportion of inadequate blood draws and TST reading times, which were slightly shorter than optimal.
Drugs may delay breast cancer progression. In a study published online by the New England Journal of Medicine December 7, two drugs showed promise in delaying the worsening of late-stage breast cancer. Pertuzumab, manufactured by Genentech, and everolimus, made by Novartis, both may prolong the lives of women who are battling an advanced stage of the disease. In the trial of pertuzumab, used in combination with the chemotherapy drug docetaxel and Genentech's Herceptin in women with tumors that have elevated levels of the protein Her2, the median time of progression of the disease was 18.5 months, as opposed to 12.4 months for patients given a placebo. In the trial of everolimus, women who took it along with the drug exemestane had a median progression time of 7.4 months, as opposed to 3.2 months for patients who took exemestane and a placebo.
Researchers stressed that more data were needed before definitive conclusions could be drawn. But Dr. Jos'e Baselga, a principal investigtor in both studies and a consultant to both companies, called the results “clinically meaningful.” Whether Food and Drug Adminstration approval is in the offing for either drug is uncertain, however. Observers noted that the FDA recently revoked earlier approval of Genentech's Avastin, which had been originally approved because it delayed tumor progression by 5.5 months in trials—but was later shown to have little effect in prolonging lives.
Molecular Diagnostics
New Randox molecular diagnostic test enables selection of CRC patients for anti-EGFR therapy. Colorectal cancer (CRC) is the third most common cancer worldwide, and metastatic disease accounts for 40% to 50% of newly diagnosed patients. Despite recent therapeutic advances, the prognosis for metastatic CRC remains poor. Early diagnosis and assignment of the most appropriate therapy pathway is therefore crucial. UK-based Randox recently unveiled its KRAS/BRAF/PIK3CA array, designed to allows the clinician to select appropriate patients for anti-EGFR therapy.
Monoclonal antibodies (MoAbs) targeting the epidermal growth factor receptor (EGFR) have proven effective in combination with chemotherapy or as single agents for treatment. However, only a subset of patients with metastatic CRC clinically benefit from EGFR-targeted MoAbs. Mutations in the KRAS gene are known to disrupt the EGFR pathway, rendering the anti-EGFR therapy ineffective. Presence of KRAS mutations accounts for approximately 35% to 45% of non-responsive patients. Oncogenic mutations in genes encoding key downstream effectors within the EGFR signalling pathways may also be responsible for resistance to EGFR-targeted MoAbs. Mutations within the BRAF and PIK3CA genes have now been reported to affect patient response to EGFR-targeted MoAbs. The KRAS/BRAF/PIK3CA Array is designed for the rapid qualitative detection of point mutations within the genes KRAS, BRAF and PIK3CA from tissue DNA. It is compatible for use with a range of genomic DNA input and type, a single sample is required for testing, and results are obtained in three hours.
Webinar
“An Update on Clinical Applications for Vitamin D Assays” is the title of a webinar to be presented by the American Association for Clinical Chemistry (AACC) to be held on January 26, 2012, at 2:00 p.m. EST. The webinar is timely, as concern is growing in the United States and worldwide about an increasing incidence of vitamin D deficiency in children and adults. In children, it is a common cause of bone deformities, and in adults it can lead to bone loss and osteoporosis. Beyond bone health, other effects are also being studied.
Vitamin D deficiency is leading to increased clinician demands for vitamin D testing. Laboratorians face two related considerations: application of the test results by the patient's physician; and bringing the testing in-house. Vitamin D testing has traditionally been outsourced, but now many labs are considering performing the tests themselves.
The webinar will feature two experts: Mark D. Kellogg, PhD, DABCC, FACB, Associate Director of Chemistry, Children's Hospital, and Assistant Professor of Pathology, Harvard Medical School in Boston, MA; and Michael Kleerekoper, MD, MACE, Clinical Professor, Departments of Internal Medicine and Obstetrics & Gynecology at Wayne State University School of Medicine in Detroit, MI and Chief Medical Officer, MicroMRI, Inc. in Langhorne, PA. They will address key issues facing the laboratory: understanding today's testing technologies and learning how to consult effectively with clinicians to interpret test results.
