PrePex protects
February 27, 2012
by Emily Ornberg, contributing writer
A new appliance as a simple as a rubber band holds the promise of dramatically lowering the rate of deaths by HIV infection. The device, called the PrePex, is used to carry out one of the world’s oldest surgical procedures, one that may help prevent HIV: male circumcision.
The World Health Organization and the Joint United Nations Programme on HIV/AIDS recommended mass circumcision to African nations in 2007 as part of a comprehensive prevention package to be used against HIV, according to Dr. Vincent Mutabazi, a physician who works with the Rwanda Ministry of Health and the Rwanda Biomedical Center, heads HIV research in Rwanda and was the principal investigator in recent clinical trials of the PrePex.
“The PrePex device is a simple solution to a very big problem that we have in this part of the world,” Mutabazi explained in a telephone interview from Rwanda.
To date, HIV has taken the lives of 25 million people, a rate of 2 million per year. Two-thirds of these deaths have been in sub-Saharan Africa.
Studies show that circumcision is one of the most effective “vaccines” against the AIDS virus, reducing the risk of HIV infection in men by at least 60 percent. In a circumcised individual, the open skin on the head of the penis provides a thick protective barrier stemming from keratin, a tough structural protein found in hair and fingernails. But on the inner surface of the foreskin, the keratin layer is much thinner, resembling the interior lining of the mouth or eyelid.
The inner foreskin also contains immune system cells called Langerhans cells.
“These are the cells that can precipitate the entry of [HIV] infection for individuals that are not circumcised,” Mutabazi said.
Without the keratin barrier, he said, HIV easily accesses these foreskin cells, which can transport the virus to neighboring lymph nodes that allow HIV to spread to other immune system cells.
Based on these recent discoveries, African officials hope to circumcise 20 million men by 2015 to help curb the AIDS epidemic plaguing the continent. However, a lack of trained doctors and insufficient funding has limited the procedure to only 600,000 men so far.
“We spread the message of abstinence, faithfulness to one person only, condom use and circumcision,” Mutabazi said.
The PrePex was developed by Circ MedTech, a start-up founded by Dr. Oren Fuerst, one of the device’s inventors, and his wife, Tzameret, to facilitate “safe, simple, scalable and cost effective non-surgical adult male circumcision programs as part of a comprehensive HIV prevention package,” according to the firm’s website.
While many parts of the world perform male circumcision at birth for religious or cultural reasons, the practice is not common in Rwandan culture. Consequently, a very large number of adults are uncircumcised, Mutabazi explained.
From the three initial clinical studies done so far, the PrePex has proven to be faster, less painful and less bloody than any other form of circumcision, especially the traditional surgical procedure. The PrePex’s advantage is its use of a tight, rubber band-like ring to block blood flow to the tissue. The foreskin dies within hours from lack of blood and falls off or can be clipped off after a week. This process has been compared to the way the remnants of the umbilical cord shrivel up and fall off days after being snipped.
Nurses can peform the procedure with as little as three days’ training, which will allow the limited number of doctors to do more complicated surgeries, Mutabazi said.
“And then, because of the fact that we will have so many more nurses who will be trained, we will be able to complete more circumcisions in a faster amount of time,” he said.
One study carried out under WHO supervision reportedly demonstrated the superiority of the PrePex over traditional male circumcision in multiple areas, including procedure time, which WHO defined as “the primary endpoint.”
Placement of the device takes an average of three minutes, approximately an 80 percent improvement on the surgical procedure. The PrePex requires no sterile facilities or settings and is said to be easy to ship and store.
Originally, Mutabazi didn’t forsee Africa’s circumcision goal being achieved by 2015, but said with the introduction of the PrePex, the goal might be reached.
“Someone once said that this device is a ‘game changer,’” he said. “It’s the way to go forward with circumcision at this point.”
Johnathon Briggs, spokesman for the AIDS Foundation of Chicago, agreed that the device could be instrumental in preventing the spread of HIV.
“Scaling up voluntary medical male circumcision could have a major impact on rates of new HIV infections, especially in sub-Saharan Africa where the primary mode of transmission is heterosexual contact,” Briggs said.
Although the Rwandan Ministry of Health is still waiting for WHO’s approval of the device for production, Mutabazi said the results they have seen from the clinical trials suggest the PrePex device is considered to have come at a perfect time.
“We are very, very excited,” said Dr. Agnes Binagwaho, Minister of Health of Rwanda. “The PrePex is revolutionary.”