Challenge trials for Covid-19 vaccine are being planned (and a recent NBER cost/benefit analysis)

from Market Design at https://bit.ly/3jI0CqP on October 30, 2020 at 01:04PM

 Here’s the NY Times:

To Test Virus Vaccines, U.K. Study Will Intentionally Infect Volunteers–The hotly contested strategy of deliberate exposure, known as a human challenge trial, could speed up the process of identifying effective coronavirus vaccines.  By Benjamin Mueller

"Scientists at Imperial College London plan to deliberately infect volunteers with the coronavirus early next year, launching the world’s first effort to study how vaccinated people respond to being intentionally exposed to the virus and opening up a new, uncertain path to identifying an effective vaccine.

"The hotly contested strategy, known as a human challenge trial, could potentially shave crucial time in the race to winnow a number of vaccine candidates. Rather than conducting the sort of trials now underway around the world, in which scientists wait for vaccinated people to encounter the virus in their homes and communities, researchers would purposely infect them in a hospital isolation unit.

"Scientists have used this method for decades to test vaccines for typhoid, cholera and other diseases, even asking volunteers in the case of malaria to expose their arms to boxes full of mosquitoes to be bitten and infected. But whereas the infected could be cured of those diseases, Covid-19 has few widely used treatments and no known cure, putting the scientists in charge of Britain’s study in largely uncharted ethical territory.

"The volunteers in London will be paid roughly Britain’s minimum wage, which is about £9, or $11, per hour, for their time in taking part in the trial and their two to three weeks in mandatory quarantine. The researchers said they were wary of offering additional incentives that could cloud the judgment of volunteers."

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And here’s a recent NBER paper on the efficiency of challenge trials:

A Cost/Benefit Analysis of Clinical Trial Designs for COVID-19 Vaccine Candidates

Donald A. Berry, Scott Berry, Peter Hale, Leah Isakov, Andrew W. Lo, Kien Wei Siah & Chi Heem Wong

ID w27882, DOI 10.3386/w27882, October 2020

Abstract: We compare and contrast the expected duration and number of infections and deaths averted among several designs for clinical trials of COVID-19 vaccine candidates, including traditional randomized clinical trials and adaptive and human challenge trials. Using epidemiological models calibrated to the current pandemic, we simulate the time course of each clinical trial design for 504 unique combinations of parameters, allowing us to determine which trial design is most effective for a given scenario. A human challenge trial provides maximal net benefits—averting an additional 1.1M infections and 8,000 deaths in the U.S. compared to the next best clinical trial design—if its set-up time is short or the pandemic spreads slowly. In most of the other cases, an adaptive trial provides greater net benefits.