By Sara Miller, NoCamels -
Thanks to advances in health, medicine and diet, we are all living longer. And maintaining quality of life as we age often means replacing parts of our bodies that become worn over time.
Joint replacements in particular have become increasingly common. In the US alone, close to 3 million hip and knee replacements are carried out every year, according to the American Joint Replacement Registry.
While most of these procedures take place without further incident, around 2 percent of patients experience an infection at the implant site that cannot be treated with antibiotics. And although this is only a small proportion of the total number of patients, in real terms it affects thousands of people each year.
The difficulty in treating these infections is due to a biofilm – a thin layer of cells that bacteria use to protect themselves against attack – that forms at the infection site and even on the implant itself.
Until now, removing the biofilm in order to treat the infection has required more surgery, but Israeli medtech startup Dimoveo Medical has found a way of using iron nanoparticles to clean away the biofilm with a far shorter and less invasive procedure.
“Once you get into that position where you have an infection which is untreatable with antibiotics, you go back into the operating room and you reopen the surgery,” Yair Ramot, founder and CEO of Dimoveo, tells NoCamels.
After the surgical site has been reopened, the implant and the infected area in the body are rinsed with copious amounts of saline to clear the biofilm so that antibiotics can be administered.
Unfortunately, Ramot says this procedure only works for about half of those suffering from infection at the implant site.
“They are washing it with a lot of saline and a lot of prayers, because 50 percent of those patients come back again with another infection. It doesn’t go away,” he says.
And if the infection does return, the steps to remove it become far more invasive, with another operation that involves taking the implant out altogether, and thoroughly cleaning and removing any trace of bacteria from it and the surgical site.
The implant is only reinserted three months later, according to Ramot, and only if the site is still free of infection.
Even with this drastic step, there is a 25 percent chance that the infection will return, he explains.
“Then you go into chronic infection, meaning you have to take antibiotics for the rest of your life. It’s a really bad situation,” Ramot says.
Dimoveo’s proprietary solution is to partially reopen the surgical site and fill the area with a saline solution containing the iron nanoparticles. The nanoparticles are then hit by ultrasound waves, sending them spinning around at high speeds to destroy the biofilm and enable the infection to be treated by antibiotics.
“I would call it a sandblasting effect on a nanoscale,” says Ramot. In fact, the name Dimoveo derives from the Latin word for remove or extract.
The entire process, which is carried out under anesthesia, takes less than an hour. Both it and the recovery period of several weeks are significantly shorter than for the options that were previously available, says Ramot.
Having decided to move away from using increasingly aggressive medications in an effort to penetrate the biofilm, Dimoveo, which was founded in 2020, took the approach of removing the layer altogether using mechanical energy, washing it away and opening the door for antibiotics to be used effectively.
The idea for the actual process to clean the biofilm came from a doctor of physics who built on the existing use of ultrasound by adding the nanoparticles. Iron was chosen for the nanoparticles as they had already been approved by the US Food and Drug Administration, explains Ramot, himself an experienced entrepreneur in the medical device field and who has degrees in both biomedical and mechanical engineering.
Dimoveo is for now focused on knee implants. But Ramot says that the procedure is suitable for any kind of joint replacement, such as knee, hip, ankle, shoulder and spine, as well as bone fractures that require screws or a plate to be inserted.
“We decided to start with the knee, because this is the most common and the most easy [procedure] to prove our efficacy,” he says.
Most of the funding for the development process came from the Israel Innovation Authority, the government department dedicated to advancing the national tech sector on the international stage, as well as the Israeli medtech incubator MEDX Xelerator, whose offices in the central city of Or Yehuda are also home to Dimoveo.
“Working in MEDEX is very good,” Ramot says. “There’s a lot of support.”
The startup is currently aiming to raise an additional $5.5 million to see it through its clinical studies, which it plans to complete at medical centers in Israel, Michigan and Helsinki. And Ramot admits that Israel’s ongoing war with Gaza, triggered by the massive October 7 terror attack by Hamas, has made fundraising a challenge.
Dimoveo has already carried out non-human studies at a hospital in Pittsburgh to show that the nanoparticles can successfully clear the biofilm and that the method itself is completely safe for a patient who has already been through a painful surgical procedure. It also showed that orthopedic surgeons can incorporate the process into their current standards of care.
Dimoveo is also preparing to submit a request for approval from the FDA, a vital step for marketing the device in the United States.
That startup plans to commercialize the device in mid-2025, aiming to find a strategic partner in the form of a large, established company in the field in order to help penetrate the market.
Once this has been achieved, Ramot explains that the next step will be to create a next generation product that could be incorporated into the initial joint replacement surgery to stop any infection taking hold at all.
“We don’t do any harm to healthy tissue; we don’t do any harm to the implant itself,” Ramot says. “This is very important.”
