In mid-2017, two groups of 15 strangers lived together for 28 days each in a ring of shipping containers assembled in the parking lot of Antwerp University Hospital in Belgium. They had access to books and movies, a small courtyard for barbecues, a common kitchen and dining room, and a fitness room — all of it behind secure interlocking doors and under the watch of personnel in protective gowns.

 

What sounds like a reality TV or sci-fi scenario was, in fact, a remarkable clinical trial of the latest weapon in the battle to eradicate polio — a reengineered vaccine called the novel oral polio vaccine type 2, or nOPV2. The study aimed to evaluate whether the altered formula, the first major update to polio vaccines in about six decades, could help end outbreaks of circulating vaccine-derived poliovirus, also known as variant poliovirus. Such cases arise in rare instances when the live but weakened virus contained in oral polio vaccines circulates in areas of low vaccine coverage and mutates back into a dangerous form that can infect people who have not been fully vaccinated.

These variant poliovirus outbreaks have emerged over the past two decades as a significant stumbling block in the effort by Rotary and its partners in the Global Polio Eradication Initiative (GPEI) to wipe out the disease. The outbreaks are different from those driven by wild poliovirus, which circulated naturally in the environment for millennia and remains endemic in just two countries, Afghanistan and Pakistan. But the outcome is the same — the virus in either kind of outbreak can, in rare instances, cause paralysis.

 

In 2011, staff at the Bill & Melinda Gates Foundation, one of the GPEI partners, wondered if the live virus in the traditional oral vaccine could be tweaked to limit its ability to mutate. "The first challenge was purely scientific," says Ananda Bandyopadhyay, a deputy director of the polio team at the Gates Foundation, which funded and led the effort. "How do you make the vaccine more genetically stable without compromising its immunogenicity [ability to provoke an immune response]? That was really, really challenging."

 

Even then, researchers would need to figure out how to test the idea. Any attempt would require strict isolation of study participants. At a 2015 meeting in Brussels, Bandyopadhyay pitched the audacious idea to Pierre Van Damme, director of the Centre for Evaluation of Vaccination at the University of Antwerp. "We had to be very creative," says Ilse De Coster, who would lead the clinical trial team with Van Damme in Belgium, "because at that time we didn't have any facility that was developed for containment."

 

Click here for the full story: A new weapon against polio | Rotary International