Design of ebola vaccine trials in west africa sage journals. The statistical power and validity of ebola vaccine trials. This candidate has been administered to people at risk of ebola virus disease in the democratic republic of the congo drc and was previously tested in niaidsupported clinical trials in west africa. The most advanced filovirus vaccine approaches target ebov with multiple phase 14 human trials using primeonly and. Jul 22, 2019 the t cell mediated responses to the ad26. A vaccine against ebola has been shown to be 100% successful in trials conducted during the outbreak in guinea and is likely to bring the west african. Army medical research institute of infectious diseases were already engaged in human phase i 2 trials of ebola vaccines, and an nih partnership was establishing a phase iiiii doubleblind, randomized, placebocontrolled trial in liberia of two of the leading ebola vaccine candidates. Phase ii trials of the two most advanced vaccines against ebola virus disease will begin in west africa in the next two to four weeks, the world health organization has announced. Scientists battling the deadly ebola virus are poised for a breakthrough in the new year after an experimental vaccine shot proved to be 100percent effective during a trial in west africa and. Vaccine trials aim to assess vaccine safety and immunogenicity in phase i. Trials of ebola vaccine set to begin in west africa the bmj. Among other studies of this vaccine, the partnership for research on ebola vaccines in liberia i prevail i randomised, doubleblind, placebo. The inside story of how scientists produced an ebola vaccine.
Ebola vaccine trial proves 100% successful in guinea. Original article from the new england journal of medicine phase 1 trials of rvsv ebola vaccine in africa and europe. Ebola crisis deepens with 2nd death in major congo city more in ebola virus outbreak the vaccine was developed by the canadian government and. Julie ledgerwood, do, chief of the clinical trials program at the niaid vaccine research center and the studys primary investigator, said in an niaid statement that earlier studies suggested that cd8 t cells played a key role in protecting vaccinated animals who received a lethal ebola dose. The west african ebola epidemic has set in motion a collective endeavour to conduct accelerated clinical trials, testing unproven but potentially lifesaving interventions in the course of a major public health crisis. The 2014 outbreak of evd in west africa is the largest ever.
Pdf phase 1 trials of rvsv ebola vaccine in africa and. Jan 26, 2017 africancanadian study of hivinfected adults and a vaccine for ebola achiv ebola the safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Ebola vaccine trials could start in africa in january. Whereas multiple vaccine candidates for ebola virus ebov are now in human phase iiii clinical trials 129 1, only a limited number of lassa virus lasv vaccine approaches are under. The vaccine used in this study is made from small parts of ebola genetic material. One of the most common critiques was that the vaccine trials would lead to ebola cases in ghana. Questionable efficacy of the rvsvzebov ebola vaccine the.
Ebola test vaccines appear safe in phase 2 liberian. Deliberations on design options for clinical trials to assess the safety and efficacy of investigational ebola vaccines. Out of 9 articles in our dataset, 47 33% claimed that the vaccine would cause an ebola outbreak in ghana, while 27. Prevention of ebola virus disease through vaccination. Oct 17, 2014 ebola vaccine trials raise ethical issues. We read with great interest the final report by ana maria henaorestrepo and colleagues feb 4, 2017, p 5051 on the ring vaccination trial of an rvsvvectored vaccine for ebola virus disease rvsvzebov. This is generally a severe disease which can also lead to death. The device was modified and designated as arktek df. Jul 08, 2016 study sites and enrollment through october 2015 for the sierra leone trial to introduce a vaccine against ebola. At the start of the study, half of the people in the study about 1,500 people will get the ebola vaccine and the rest of the people will get a placebo dummy vaccine that looks like a real vaccine but does not have active components in it. During the outbreak, clinical trials of the investigational ebola vaccine rvsv.
Out of 9 articles in our dataset, 47 33% claimed that the vaccine would cause an ebola outbreak in ghana, while 27 articles 19% said this would not happen. Phase 1 trials of rvsv ebola vaccine in africa and europe. The design and analysis of phase iib ebola vaccine trials. Trials of ebola vaccines could begin as early as january in the west african countries most affected by the virus, a world health organization official said tuesday. Oct 17, 2014 ebola virus causes an infection known as ebola virus disease evd. Eu contribution to ebola vaccine development and trial in drc supporting clinical trials the eu will support the critical clinical study of the janssen ebola vaccine in the democratic republic of congo drc with 6 million, through an existing agreement with the coalition for epidemic preparedness. A substudy of the ebola ca suffit trial addressed vaccine performance among frontline workers flws, defined as those actively working to respond to the ebola epidemic and who, through their daily work, were considered highrisk for ebola exposure.
Ebola vaccines are a number of vaccines to prevent ebola that are either approved or in development. It had been used extensively in kivu ebola epidemic under a compassionate use protocol. Apr 12, 2019 while the vaccine is still unlicensed, a clinical trial conducted in guinea near the end of the west african ebola outbreak showed the vaccine was highly efficacious. The nih is helping guide two frontrunner ebola vaccine candidates through earlystage human trials and, barring safety or immunity problems, may have the vaccines ready for advanced testing in african and other volunteers as early as december, according to nih officials. Indeed, some scientists believe that the epidemic has grown so large that vaccines will be essential to stopping it. This unprecedented effort was supported by the recommendations of an ad hoc ethics panel convened in august 2014 by the who. Preliminary results on the efficacy of rvsvzebovgp ebola vaccine using the ring vaccination strategy in the control of an ebola outbreak in the democratic republic of the congo. Ebola vaccine trial suspended over unexpected side effects. Phase 1 trial of ebola vaccine in mali full text view. Volunteers in the ring vaccination trial are observed during 30 min after vaccination and subsequently visited at home by medical teams on days 3, 14, 21, 42, 63, and 84 post vaccination. Overall, the ebola vaccine trials displayed better coordination and cooperation among international researchers, regulators, manufacturers, funders, and the national authorities and communities of the ebola affected countries than did the therapeutic trials. The guinea trial follows good clinical practice guidelines with clearly defined procedures to ensure the safety of the study participants. Fda announced today the approval of ervebo, the first fdaapproved vaccine for the prevention of ebola virus disease evd, caused by zaire ebolavirus in individuals 18 years of age and older. The drcs health ministry on saturday said preliminary results from the clinical trial under way alongside the ring vaccination in the outbreak region confirm earlier high efficacy observations seen in guineas outbreak in 2015.
Coalition for epidemic preparedness innovations cepi, and others to support the development and licensure. The devastating ebola virus ebov epidemic in west africa in 202016 accelerated the progress of several vaccines and antivirals through clinical trials, including the replicationcompetent vesicular stomatitis virusbased vaccine expressing the ebov glycoprotein vsvebov. The ebola virus causes a disease called ebola hemorrhagic fever. The gush of new infections pushes the drcs ebola total to 1,264 cases, 1,198 of them confirmed and 66 listed as probable. Vaccine trails without placebo arm or randomization perspective with matched comparison arm case control with matched controls. Human trials testing the safety of an ebola virus vaccine were recently begun by researchers from the vaccine research centre vrc at the national institute of allergy and. First fdaapproved vaccine for the prevention of ebola virus. A number of clinical vaccine trials were conducted in the affected countries during the epidemic 4,5,6,7. Comahs college of medicine and allied health sciences, university of sierra leone. Strive sierra leone trial to introduce a vaccine against ebola. The first vaccine to be approved in the united states was rvsvzebov in december 2019.
Ebola virus disease candidate vaccines under evaluation in. Jan 07, 2020 mariepaule kieny, who then headed the division of the who tasked with trying to spur development of drugs and vaccines for diseases like ebola, noted the company had never conducted a clinical trial. However, multiple investigational ebola vaccines have been tested in numerous clinical trials around the world. Oct 20, 2016 the 2014 ebola epidemic has significantly accelerated the development of ebola vaccines, 46 clinical trials with ebola vaccines were launched according to the registration on clinicaltrial. Ebola vaccine shows very impressive performance in outbreak. Come january, as many as 20,000 doses of an ebola vaccine candidate may be ready for testing in the unprecedented epidemic racing through west africa. Phase i clinical trials with this replicating vectored.
Ebola vaccine fasttracked after proven 100% effective in. Nov 05, 2003 experimental ebola vaccine trial the safety and scientific validity of this study is the responsibility of the study sponsor and investigators. The team included members of the countrys national ethics committee nec. Niaid has supported the development of various candidates, including the rvsvzebov vaccine developed by merck.
Ebola virus ebov, representing the zaire ebolavirus species within the family filoviridae, has been responsible for multiple outbreaks of ebola virus disease evd since 1976. Epidemics, including experts deliberations on future clinical trials for candidate ebola vaccines. The statistical power and validity of ebola vaccine trials in. Update with the development of ebola vaccines and implications of. Briefly, among 2119 people who received the vaccine immediately, no cases of ebola virus disease were identified in a period of 11 days 1021 days after vaccination. Cold chain for storage and transport of vaccine oxford academic. Use of chad3eboz ebola virus vaccine in malian and us adults, and boosting of malian adults with mvabnfilo. Zebov mvabn filo vaccine at baseline and day 77 in a subset of participants will be measured by the percentage of memory cd4 and cd8 t cells responding to ebola gp and np peptides by production of ifngamma andor il2 andor tnf.
Based on these findings, the study, which is sponsored by the. Ebola cases climb by 44 as vaccine trial affirms high. Several promising vaccine candidates have been shown to protect nonhuman primates against lethal infection. Those at highest risk contacts of known ebola cases, and their contacts should get 0. One lasting legacy of strive is that the cold chain infrastructure, specialized equipment, and local staff expertise are now available in sierra leone for handling. Wed like to understand how you use our websites in order to improve them. Strive sierra leone trial to introduce a vaccine against. First human trial of nihgsk ebola vaccine shows promise. We did not identify any studies evaluating ebola vaccine efficacy trial design. The vaccineand another one whose development is 6 weeks behindcould bring hope to a desperate, panicked population. Mariepaule kieny, assistant director general at who, told a press briefing on 9 january that safety trials had been successfully conducted on the two vaccines. Pdf the ebola epidemic that broke out in west africa towards the end of 20 had been brought under reasonable control by 2015.
Phase 1 trials of rvsv ebola vaccine in africa and europe preliminary report article pdf available in new england journal of medicine 37417 april 2015 with 516 reads how we measure reads. Vaccine trials may take months or years to complete, since a sufficient time period must elapse for the subjects to react to the vaccine and develop the required antibodies. Symptoms begin with fever and muscle aches and progress to breathing problems, severe bleeding, kidney problems, and shock. Study sites and enrollment through october 2015 for the sierra leone trial to introduce a vaccine against ebola. We evaluate the statistical validity and power of randomized controlled rct and steppedwedge cluster trial swct. This article describes some of the most controversial issues that arose in designing phase 2 and. The wg recommended that there should be alignment of different initiatives e. Statistical power and validity of ebola vaccine trials in.
The clinical phase i trial of a potential vaccine against the dreaded ebola virus has been successfully completed at four partner sites in africa and europe. Factors influencing participation in an ebola vaccine trial. Researchers want to develop a vaccine to prevent ebola infection. Strive, however, is not an swct, but a phasedrollout trial in which randomisation to immediate or delayed vaccination groups occurs at the individual level a randomised clinical trial rct. Matz, andrea marzi and heinz feldmann laboratory of virology, division of intramural research, national institute of allergy and infectious diseases, national institutes of health, rocky. The design and analysis of phase iib ebola vaccine trials ira longini. Africancanadian study of hivinfected adults and a vaccine.
An experimental ebola vaccine seems to confer total protection against infection in people who are at high risk of contracting the virus, according to the preliminary results of a trial in guinea. Matz, andrea marzi and heinz feldmann laboratory of virology, division of intramural research, national institute of allergy and infectious diseases, national institutes of health, rocky mountain laboratories, hamilton, mt, usa abstract. Eu contribution to ebola vaccine development and trial in drc. Equipment inventoried during this visit, in at least one of. For each of 300 combinations of assumed vaccine efficacy, protective delay, trial design, start date, and hazard levels, we simulated 2000 trials totalling 600 000 trials, with each trial based on a unique set of stochastically generated districtlevel ebola virus disease projections for sierra leone. A highly anticipated test of an experimental ebola vaccine will begin this week at the national institutes of health. Prevention of ebola virus disease through vaccination the lancet. You will get the ebola vaccine, either at the start of the study, or after 6 months into the study.
Gzebovgp vaccine reported 100% vaccine efficacy, paving the way for use of this vaccine in response to confirmed ebola cases. An investigational vaccine called rvsvzebov, which has shown to be safe and protective against the zaire strain of the ebola virus, is recommended by the strategic advisory group of experts on immunization sage 1 for use in ebola outbreaks caused by the zaire strain of the virus, in the event where there is no licensed vaccine. Ebola vaccine development international journal of infectious. The prevac vaccine study, being conducted in west africa, is a large, randomized, placebocontrolled phase 2 clinical trial to assess the safety and ability of three different ebola vaccine strategies to stimulate an immune response to the virus that may protect against ebola virus disease. Ebola vaccines in future outbreaks, and, if yes, can sage make recommendations on how these might be addressed. Jun 18, 2018 the devastating ebola virus ebov epidemic in west africa in 202016 accelerated the progress of several vaccines and antivirals through clinical trials, including the replicationcompetent vesicular stomatitis virusbased vaccine expressing the ebov glycoprotein vsvebov. Safe and effective vaccines may help end the ongoing ebola virus disease evd epidemic in west africa, and mitigate future outbreaks. The vaccine is planned for use in a phase 1 clinical trial in japan and is the only wholevirus ebola vaccine candidate under development. It will be produced at waisman biomanufacturing, a specialized facility whose mission is to help translate scientific discovery into earlystage clinical trials. Implementing an ebola vaccine study sierra leone mmwr. The 20142016 west africa ebola virus disease outbreak was unprecedented in magnitude and complexity, resulting in 28,000 cases and 11,000 deaths in the 3 highly affected countries sierra leone, guinea, and liberia.
Ebola is a rare but deadly virus that causes fever, body aches, and diarrhea, and sometimes bleeding inside and outside the body as the virus spreads through the body, it damages the immune. The vesicular stomatitis virusbased ebola virus vaccine. But it was also decided that in order to use the donated canadian vaccine, clinical trials first had to assess its safety and establish the appropriate. This information is especially important given that the pathway to licensure for an ebola virus vaccine, in the absence of definitive efficacy data in human clinical trials, might involve alternative regulatory pathways and could require postlicensure assessment of safety and clinical. Listing a study does not mean it has been evaluated by the u. The 20142016 ebola virus disease outbreak in guinea, liberia, and sierra leone included more than 28,000 cases and more than 11,000 deaths. Thus, vebcon initiated doseescalation phase 1 clinical trials in germany, kenya. We found methodological papers describing power analyses for steppedwedge trials swct and randomized controlled trials rcts, and studies assessing trial design for evaluation of candidate vaccine efficacy for other infectious diseases. The death toll from the disease also shot higher, with 42 more fatalities reported, including a stillborn baby in beni whose mother died at the ebola treatment center. Articles efficacy and effectiveness of an rvsvvectored. Nov 12, 2019 mercks vaccine, which is marketed under the name ervebo and known to researchers as rvsvzebovgp, was tested in a clinical trial conducted in guinea towards the end of the 201416 ebola. New trial launched in west africa to evaluate three.
This candidate has been administered to people at risk of ebola virus disease in the democratic. Doubleblinded, randomized, placebo control trial rct 2. In november 2014, imi responded very rapidly to the west africa outbreak of ebola by allocating 280 million to a comprehensive call for proposals to tackle a wide range of challenges in ebola research, including vaccines development, clinical trials, storage and transport, as well as diagnostics and treatments. First fdaapproved vaccine for the prevention of ebola. The infection may be mild, but it can also lead to death. Human trial of experimental ebola vaccine starts soon cnn. The scale of the outbreak was unprecedented and prompted the development of prophylactic vaccine candidates 2,3,4.
Successful ebola vaccine provides 100% protection in trial. Strive sierra leone trial to introduce a vaccine against ebola strive the safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Mvabnfilo, a quadrivalent vaccine encoding the gps from both ebov and sudv, and also the gp from marburg virus and the np from the tai forest strain of ebola virus, was the first poxvirus vaccine to be tested in clinical trials. A number of different vaccine platforms are being developed by assessing preclinical efficacy in animal models and expediting clinical development. When used at high doses in humans, the rvsvzebov ebola vaccine elicited antibodies against. A dozen candidate vaccines including monovalent, bivalent or multivalent candidates underwent or are actively undergoing clinical development at different trial phases. Currently there are no licensed vaccines to prevent ebola virus disease. Jolanta piszczek and eric parlow1 outlined expected benefits of a steppedwedge cluster trial swct design, with specific reference to the sierra leone trial to introduce a vaccine against ebola strive. It is impossible for someone to get an ebola infection from this vaccine. Action represents another milestone for the global partnership against ebola merck nyse. The sierra leone trial to introduce a vaccine against ebola strive randomized participants without blinding to immediate or deferred 1824 weeks postenrollment vaccination. Vaccine trials without placebo arm step wedged design with randomized clusters or populations opportunistic step wedged design 3. Poliomyelitis, a viral disease, has the potential to damage the.
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