Randomized Single-Blinded Study to Evaluate Safety and Immunogenicity of Recombinant Plague Vaccine...
Plague VaccineMulticenter, randomized, single-blinded comparison of two formulations of the rF1V vaccine at a single dosage of 80 µg and two 3-dose schedules in 400 healthy, adult volunteers in four parallel cohorts. Two rF1V vaccine cohorts (N=160 each) and two rF1V antigen-only cohorts (N=40 each) will be vaccinated at two different three-dose schedules (Days 0, 56 and 182 or Days 0, 56 and 121).
A Clinical Trial to Evaluate the Safety and Efficacy of Ciprofloxacin in the Treatment of Plague...
PlaguePlague is a severe, life-threatening disease. Plague occurs in focal locations worldwide, but over 95% of human cases reported to WHO are by countries in Africa. The most common clinical manifestations of human infection are bubonic, septicemic, and pneumonic plague. Untreated pneumonic or septicemic plague is fatal in over 90% of cases; untreated bubonic plague is fatal in over 50% of cases. Delayed and ineffectual treatment is a main contributor to elevated case fatality rates, which can be as high as 40%, and to the development of pneumonic plague and plague outbreaks. Streptomycin is considered the treatment of choice, and prompt administration can reduce mortality to 5% or less. However, streptomycin may cause irreversible hearing loss and vestibular damage, reversible renal damage, and it is contraindicated during pregnancy. Tetracyclines, including doxycycline, are considered effective alternatives but they are bacteriostatic and relatively contraindicated for use in children aged < 8 years and pregnant women. Ciprofloxacin is a relatively newer antimicrobial that is used extensively in clinical practice because of its broad-spectrum antimicrobial activity, excellent tissue and intracellular penetration, suitability for oral administration, and good overall tolerability. In vitro and animal studies suggest equivalent or greater activity of ciprofloxacin against Yersinia pestis when compared with streptomycin or tetracyclines. However, the efficacy of ciprofloxacin for the treatment of human plague has never been demonstrated, nor is it FDA approved for this indication. Since 2004, CDC has collaborated with the Uganda Ministry of Health (MoH) and the Uganda Virus Research Institute (UVRI) to enhance surveillance, diagnosis, and ecological control of plague in Arua and Nebbi Districts. Through these efforts, we have collected data on over 2,400 cases of clinically diagnosed plague occurring from 1999 through 2009. In 2008, UVRI and CDC staff investigated 163 suspect plague cases: 57 (35%) had laboratory-confirmed plague illness, of which 14 patients (25%) died. Because plague is a relatively rare disease that mainly affects people living in rural, impoverished areas, it receives limited attention for research and development of affordable and sustainable diagnostic and treatment options. However, because plague cannot be eradicated, and because it causes high case fatality and has the potential for widespread person to person transmission, continued research should not be neglected. The objective of this clinical trial is to conduct a randomized, open-labeled, non-inferiority study comparing the safety and efficacy of ciprofloxacin to doxycycline, the national treatment standard in Uganda for plague, in patients aged > 8 years. The primary outcome for this trial will be patient outcome 14 days from enrollment and initiation of treatment. Patient outcome will be evaluated only for those patients with laboratory-confirmed plague illness. Information gathered from this proposed study will help optimize management of naturally occurring plague in humans in many countries of the world, including Uganda and the United States, by providing clinicians with more choices for optimal antimicrobial treatment. This is particularly true in resource limited rural regions such as Uganda where intravenous or intramuscular injections are less available. Ciprofloxacin currently is being used in Uganda and other plague endemic areas of the world for treatment of other infectious conditions, including infectious diarrhea and lower respiratory infections. In Uganda, ciprofloxacin is widely available in health facilities and local drug shops, and is affordable.