BARCELONA — Leprosy post-exposure prophylaxis is the first major innovation in treatment since multidrug therapy — which stops the transmission and prevents further disabilities — was introduced in the 1980s. But organizations fighting the neglected tropical disease disagree on whether it’s really the magic bullet it’s been touted to be.
LPEP, as the innovation is otherwise known, was launched by the Novartis Foundation in 2014 and is a drug therapy consisting of a single dose of the antibiotic rifampicin. If administered to those who come into close contact with a person with leprosy — regardless of whether or not they present with leprosy symptoms: nerve damage, numbness, and loss of vision — it is 50-60 percent effective in preventing the development of the disease over the next 2 years.
Some academics, including Diana Lockwood, the U.K.’s chief leprologist and trustee of Lepra, believe it’s not an effective method, does not protect against leprosy, and presents serious ethical problems.
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Geoff Prescott, Lepra’s CEO, explained that research shows LPEP doesn’t work on those with multibacillary leprosy — the more severe form, which includes some of the most infectious cases.
“We’re nervous of rolling out a single dose of rifampicin, which is being explained accidentally as magic bullet scenario when it’s not going to seemingly touch the people who are actually spreading the disease inadvertently,” Prescott said.
LPEP is included in the World Health Organization’s guidelines for the diagnosis, treatment and prevention of leprosy and has so far been rolled out in eight countries.
Dr. Peter Steinmann, public health specialist and epidemiologist at the Swiss Center for International Health, said that careful consideration and discussion is only natural for this new therapy. “It’s been a long time since we’ve had much advancement in leprosy treatment and control, which means some people are very eager and push very hard for the uptake of that intervention and that naturally provokes some skepticism among others,” he said.
Leprosy’s reputation as a disease of the past — and the fact that WHO declared the disease eliminated as a global public health problem in 2000 — has stymied efforts to continue fighting against it. This has led to a plateauing of case detection for more than 10 years, according to Geoff Warne, CEO of the International Federation of Anti-Leprosy Associations. While this could indicate numbers aren’t rising, organizations such as Lepra disagree, saying that there are 3 million living undiagnosed on top of the 600 new cases diagnosed each day.
“The primary argument for LPEP is that it helps to prevent the development of the disease, which if developed, is stigmatized,” Steinmann said, adding that in many societies there is a big issue of social acceptance and limited possibilities to work for those with leprosy.
The arguments against the use of LPEP: Increased stigma
Stigma is one of the reasons some believe LPEP shouldn’t be pursued. Administering it relies on those affected by leprosy identifying people they’ve come into close contact with.
“There's concerns that if you talk to leprosy-affected people and say ‘who are your contacts and can we offer them a single dose of rifampicin or any other chemoprophylaxis’ that it exposes them because in most communities people who have leprosy don't want people to know so it puts people at risk of disclosure,” Warne said.
The disease is most prevalent in Brazil, Indonesia, and India, where laws segregate those with leprosy from work, education, and places of religion. Some consider leprosy to be a curse or punishment and sometimes send those affected to leprosy colonies. That social stigma can stop people seeking treatment when the initial signs — a small patch of numbness, ulcers, lesions, and vision problems — present.
While the process of LPEP delivery may “out” a person with leprosy, Dr. Bart Vander Plaetse, deputy director of FairMed, said there’s no better solution currently out there: “[LPEP] is not the golden bullet in leprosy control, but it's a bullet and in the absence of any other new additional tools in our toolbox, it’s something that most practitioners in the field — not practitioners in the laboratory — are eager to start implementing.”
The possibility of drug resistance
Others in the community believe the administration of an unnecessary drug, on which there are few trials on long-term effects, is not a good thing and could lead to rifampicin resistance.
“The studies I have read so far do not convince me that you can really rule out any resistance building regarding tuberculosis,” said Matthias Wittrock, managing director of plan:g, adding that the same drug is used in TB control. “I don't say it's a good or bad decision to do it, but I would say be very careful and know why you're doing it,” he said.
Vander Plaetse said that while there’s no proof to show the emergence of rifampicin resistance, there’s also no proof showing the opposite.
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“If you look at it from a scientific view, do we have enough evidence to recommend to global introduction of single dose rifampicin as part of LPEP? Many people would say no, but then if you look at anything else we do in leprosy control, it has an even lesser degree of evidence,” he said, adding that all that means is the community should continue researching new innovations.
Steinmann added that some believe reassurance the medication brings could also lead to less vigilance when looking for early signs of leprosy meaning cases go undetected for longer.
The influence of the pharmaceutical industry
Finally, ties to the pharmaceutical industry are also a deterrent. Wittrock urged the leprosy community to take a more critical look at drug therapies, something ILEP said it is already doing.
“What’s fair to say is that in the leprosy world people have drawn different conclusions and one of the hopes is that with various implementations studies that are going on, evidence will start to come out. It will then make it clear whether this is having the effect that people hope it's going to have or not,” Warne said.
“The fact that it's on the Novartis Foundation’s agenda makes many people suspicious because Novartis Foundation sounds very much like Novartis and Novartis sounds very much like big pharma, and the assumption is that nothing can be true from that side,” said Vander Plaetse, who previously worked for Novartis Foundation and believes that assumption is wrong.
However, with over 13 ILEP member organizations, as well as other initiatives, tackling leprosy and running a variety of programs, differences of opinion about the efficacy of a particular intervention is inevitable, Warne explained, who noted that the best path forward tends to become clearer as the evidence and discussion unfold.
“There are lots of international federations involved in health and it would be rare indeed to have something where everybody agreed on everything so what we have in leprosy is a convergence series,” he said.