Monday, August 19, 2013

H7N9 Vaccine Challenges

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#7579

 

 

Last June (see CIDRAP: NVAC Weighs H7N9 Vaccine Options) we learned that BARDA (the HHS' Biomedical Advanced Research and Development Authority) had given authorization to several vaccine manufacturers to go ahead with clinical trials on potential H7N9 vaccines.

 

Yesterday, Helen Branswell of the Canadian Press wrote a detailed update on where these clinical trials stand now, and what lies ahead. I would invite you to read her article in its entirety, and when you return, I’ll have more.

 

Can a usable H7N9 vaccine be made? Pending research should offer clues soon

By Helen Branswell, The Canadian Press August 18, 2013

TORONTO - Can a usable vaccine against the H7N9 bird flu virus be made? Studies that are about to start should offer clues soon, says the director of the U.S. government program spearheading the work.

 

Four flu vaccine manufacturers have started or will soon start clinical trials on H7N9 vaccines, with four more expected to conduct trials in the late fall or early winter, says Dr. Robin Robinson. The work will cost the U.S. government about $100 million.

(Continue . . .)

 

Providing some more background is Dr. Ian Mackay, who writes on China’s recent H7N9 vaccine development work, the use of adjuvants, and other related issues, in his Virology Down Under blog.

 

H7N9 vaccine update...[UPDATED]

Hat tip to Dr. Nicholas Kelly for JAMA link reminder.


Earlier in the month, Zou Yong, quality directer of China based Sinovac Biotech Ltd  the Chinese Center for Disease Control and Prevention, noted that preliminary work on an adjuvanted (see below) H7N9 vaccines was complete and are ready for safety stability and clinical trials. It has already completed been through animal testing and the vaccine seems to work in our furry little friends.

(Continue . . . )

 

As Dr. Mackay mentions in his blog, in early May we saw an analysis of some of the problems inherent in creating and deploying an  H7N9 vaccine published in JAMA, penned by CIDRAP’s  Michael T. Osterholm, PhD, MPH; Katie S. Ballering, PhD; and Nicholas S. Kelley, PhD.

 

Major Challenges in Providing an Effective and Timely Pandemic Vaccine for Influenza A(H7N9)

Michael T. Osterholm, PhD, MPH; Katie S. Ballering, PhD; Nicholas S. Kelley, PhD

JAMA. 2013;():1-2. doi:10.1001/jama.2013.6589.

Published online May 9, 2013

 

While work is being done on an H7N9 vaccine, and there are hopes that a practical one can be created, we are still a long way from having any quantity of commercial vaccine available to the public.


Which means, should the H7N9 virus threaten this fall or winter, we will be looking to NPIs (Non Pharmaceutical Interventions like social distancing, school closures, hand hygiene & masks) and neuraminidase (NA) inhibiting antiviral drugs  (NAIs) like oseltamivir (Tamiflu ®) and Zanamivir (Relenza ®) to help mitigate its impact. 

 

The creation of a safe, immunogenic H7N9 vaccine is only the first challenge. It must be mass produced, and then deployed in an orderly and efficient manner.

 

Difficult decisions will have to be made on vaccine prioritization, and global distribution.

 

If, as expected, it will require 2 shots - 4 weeks apart to confer a reasonable level of immunity, the logistics of delivering the vaccine grow even greater.

 

None of which is to suggest that the pursuit of a vaccine is a futile one.

 

While an H7N9 vaccine may not be available during the opening months of a pandemic, it would be extremely valuable in limiting the effects of the virus down the line.