Sammy Basso is one of around 400 young people in the world with progeria.
Just 400 or so people in the world live with progeria: The mutation that causes it usually arises de novo, or "of new," meaning that it is not inherited but happens spontaneously during gestation. The challenge, as with all rare diseases, is that few cases means few treatments.
"When we first started, there was absolutely nothing out there," says Leslie Gordon, a physician-researcher who co-founded the Progeria Research Foundation in 1999 after her own son, also named Sam, was diagnosed with the disease. "We knew we had to jumpstart the entire field, so we collected money through road races and special events and writing grants and all sorts of donors… I think the first year we raised $75,000, most of it from one donor."
"We have not only the possibility but the responsibility to make the world a better world, and also to make a body a better body."
By 2003, the foundation had collaborated with Francis Collins, a geneticist who is now director of the National Institutes of Health, to work out the genetic basis for progeria—that single mutation Sammy has. The discovery led to interest in lonafarnib, a drug that was already being used in cancer patients but could potentially operate downstream of the mutation, preventing the buildup of the defective progerin in the body. "We funded cellular studies to look at a lonafarnib in cells, mouse studies to look at lonafarnib in mouse models of progeria… and then we initiated the clinical trials," Gordon says.
Sammy Basso's family had gotten involved with the Progeria Research Foundation through their international patient registry, which maintains relationships with families in 49 countries. "We started to hear about lonafarnib in 2006 from Leslie Gordon," says Sammy's father, Amerigo Basso, with his son translating. "She told us about the lonafarnib. And we were very happy because for the first time we understood that there was something that could help our son and our lives." Amerigo used the Italian word speranza, which means hope.
Still, Sammy wasn't sure if lonafarnib was right for him. "Since when I was very young I thought that everything happens for a reason. So, in my mind, if God made me with progeria, there was a reason, and to try to heal from progeria was something wrong," he says. Gradually, his parents and doctors, and Leslie Gordon, convinced him otherwise. Sammy began to believe that God was also the force behind doctors, science, and research. "And so we have not only the possibility but the responsibility to make the world a better world, and also to make a body a better body," he says.
Sammy Basso and his parents.
Courtesy of Basso
Sammy began taking lonafarnib, with the Progeria Research Foundation intermittently flying him, and other international trial participants, to Boston for tests. He was immediately beset by some of the drug's more unpleasant side effects: Stomach problems, nausea, and vomiting. "The first period was absolutely the worst period of my life," he says.
At first, doctors prescribed other medicines for the side effects, but to Sammy it had as much effect as drinking water. He visited doctor after doctor, with some calling him weekly or even daily to ask how he was doing. Eventually the specialists decided that he should lower his dose, balancing his pain with the benefit of the drug. Sammy can't actually feel any positive effect of the lonafarnib, but his health measurements have improved relative to people with progeria who don't take it.
While they never completely disappeared, Sammy's side effects decreased to the point that he could live. Inspired by the research that led to lonafarnib, he went to university to study molecular biology. For his thesis work, he travelled to Spain to perform experiments on cells and on mice with progeria, learning how to use the gene-editing technique CRISPR-Cas9 to cut out the mutated bit of DNA. "I was so excited to participate in this study," Sammy says. He felt like his work could make a difference.
In 2018, the Progeria Research Foundation was hosting one of their biennial workshops when Francis Collins, the researcher who had located the mutation behind progeria 15 years earlier, got in touch with Leslie Gordon. "Francis called me and said, Hey, I just saw a talk by David Liu from the Broad [Institute]. And it was pretty amazing. He has been looking at progeria and has very early, but very exciting data… Do you have any spaces, any slots you could make in your program for late breaking news?"
Gordon found a spot, and David Liu came to talk about what was going on in his lab, which was an even more advanced treatment that led to mice with the progeria mutation living into their senior mouse years—substantially closer to a normal lifespan. Liu's lab had built on the idea of CRISPR-Cas9 to create a more elegant genetic process called base editing: Instead of chopping out mutated DNA, a scientist could chemically convert an incorrect DNA letter to the correct one, like the search and replace function in word processing software. Mice who had their Lamin-A mutations corrected this way lived more than twice as long as untreated animals.
Sammy was in the audience at Dr. Liu's talk. "When I heard about this base editing as a younger scientist, I thought that I was living in the future," he says. "When my parents had my diagnosis of progeria, the science knew very little information about DNA. And now we are talking about healing the DNA… It is incredible."
Lonafarnib (also called Zokinvy) was approved by the US Food and Drug Administration this past November. Sammy, now 25, still takes it, and still manages his side effects. With luck, the gift of a few extra years will act as a bridge until he can try Liu's revolutionary new gene treatment, which has not yet begun testing in humans. While Leslie Gordon warns that she's always wrong about things like this, she hopes to see the new base editing techniques in clinical trials in the next year or two. Sammy won't need to be convinced to try it this time; his thinking on fate has evolved since his first encounter with lonafarnib.
"I would be very happy to try it," he says. "I know that for a non-scientist it can be difficult to understand. Some people think that we are the DNA. We are not. The DNA is a part of us, and to correct it is to do what we are already doing—just better." In short, a gene therapy, while it may seem like science fiction, is no different from a pill. For Sammy, both are a new way to think about fate: No longer something that simply happens to him.
Peanut allergies affect about a million children in the U.S., and most never outgrow them. Luckily, some promising remedies are in the works.
Typically, people with peanut allergies try to completely avoid them and carry an adrenaline autoinjector like an EpiPen in case of emergencies. This constant vigilance is very stressful, particularly for parents with young children.
“The search for a peanut allergy ‘cure’ has been a vigorous one,” says Claudia Gray, a pediatrician and allergist at Vincent Pallotti Hospital in Cape Town, South Africa. The closest thing to a solution so far, she says, is the process of desensitization, which exposes the patient to gradually increasing doses of peanut allergen to build up a tolerance. The most common type of desensitization is oral immunotherapy, where patients ingest small quantities of peanut powder. It has been effective but there is a risk of anaphylaxis since it involves swallowing the allergen.
"By the end of the trial, my son tolerated approximately 1.5 peanuts," Sharon Wong says.
DBV Technologies, a company based in Montrouge, France has created a skin patch to address this problem. The Viaskin Patch contains a much lower amount of peanut allergen than oral immunotherapy and delivers it through the skin to slowly increase tolerance. This decreases the risk of anaphylaxis.
Wong heard about the peanut patch and wanted her son to take part in an early phase 2 trial for 4-to-11-year-olds.
“We felt that participating in DBV’s peanut patch trial would give him the best chance at desensitization or at least increase his tolerance from a speck of peanut to a peanut,” Wong says. “The daily routine was quite simple, remove the old patch and then apply a new one. By the end of the trial, he tolerated approximately 1.5 peanuts.”
How it works
For DBV Technologies, it all began when pediatric gastroenterologist Pierre-Henri Benhamou teamed up with fellow professor of gastroenterology Christopher Dupont and his brother, engineer Bertrand Dupont. Together they created a more effective skin patch to detect when babies have allergies to cow's milk. Then they realized that the patch could actually be used to treat allergies by promoting tolerance. They decided to focus on peanut allergies first as the more dangerous.
The Viaskin patch utilizes the fact that the skin can promote tolerance to external stimuli. The skin is the body’s first defense. Controlling the extent of the immune response is crucial for the skin. So it has defense mechanisms against external stimuli and can promote tolerance.
The patch consists of an adhesive foam ring with a plastic film on top. A small amount of peanut protein is placed in the center. The adhesive ring is attached to the back of the patient's body. The peanut protein sits above the skin but does not directly touch it. As the patient sweats, water droplets on the inside of the film dissolve the peanut protein, which is then absorbed into the skin.
The peanut protein is then captured by skin cells called Langerhans cells. They play an important role in getting the immune system to tolerate certain external stimuli. Langerhans cells take the peanut protein to lymph nodes which activate T regulatory cells. T regulatory cells suppress the allergic response.
A different patch is applied to the skin every day to increase tolerance. It’s both easy to use and convenient.
“The DBV approach uses much smaller amounts than oral immunotherapy and works through the skin significantly reducing the risk of allergic reactions,” says Edwin H. Kim, the division chief of Pediatric Allergy and Immunology at the University of North Carolina, U.S., and one of the principal investigators of Viaskin’s clinical trials. “By not going through the mouth, the patch also avoids the taste and texture issues. Finally, the ability to apply a patch and immediately go about your day may be very attractive to very busy patients and families.”
Brandon Wong displaying origami figures he folded at an Origami Convention in 2022
Sharon Wong
Clinical trials
Results from DBV's phase 3 trial in children ages 1 to 3 show its potential. For a positive result, patients who could not tolerate 10 milligrams or less of peanut protein had to be able to manage 300 mg or more after 12 months. Toddlers who could already tolerate more than 10 mg needed to be able to manage 1000 mg or more. In the end, 67 percent of subjects using the Viaskin patch met the target as compared to 33 percent of patients taking the placebo dose.
“The Viaskin peanut patch has been studied in several clinical trials to date with promising results,” says Suzanne M. Barshow, assistant professor of medicine in allergy and asthma research at Stanford University School of Medicine in the U.S. “The data shows that it is safe and well-tolerated. Compared to oral immunotherapy, treatment with the patch results in fewer side effects but appears to be less effective in achieving desensitization.”
The primary reason the patch is less potent is that oral immunotherapy uses a larger amount of the allergen. Additionally, absorption of the peanut protein into the skin could be erratic.
Gray also highlights that there is some tradeoff between risk and efficacy.
“The peanut patch is an exciting advance but not as effective as the oral route,” Gray says. “For those patients who are very sensitive to orally ingested peanut in oral immunotherapy or have an aversion to oral peanut, it has a use. So, essentially, the form of immunotherapy will have to be tailored to each patient.” Having different forms such as the Viaskin patch which is applied to the skin or pills that patients can swallow or dissolve under the tongue is helpful.
The hope is that the patch’s efficacy will increase over time. The team is currently running a follow-up trial, where the same patients continue using the patch.
“It is a very important study to show whether the benefit achieved after 12 months on the patch stays stable or hopefully continues to grow with longer duration,” says Kim, who is an investigator in this follow-up trial.
"My son now attends university in Massachusetts, lives on-campus, and eats dorm food. He has so much more freedom," Wong says.
The team is further ahead in the phase 3 follow-up trial for 4-to-11-year-olds. The initial phase 3 trial was not as successful as the trial for kids between one and three. The patch enabled patients to tolerate more peanuts but there was not a significant enough difference compared to the placebo group to be definitive. The follow-up trial showed greater potency. It suggests that the longer patients are on the patch, the stronger its effects.
They’re also testing if making the patch bigger, changing the shape and extending the minimum time it’s worn can improve its benefits in a trial for a new group of 4-to-11 year-olds.
The future
DBV Technologies is using the skin patch to treat cow’s milk allergies in children ages 1 to 17. They’re currently in phase 2 trials.
As for the peanut allergy trials in toddlers, the hope is to see more efficacy soon.
For Wong’s son who took part in the earlier phase 2 trial for 4-to-11-year-olds, the patch has transformed his life.
“My son continues to maintain his peanut tolerance and is not affected by peanut dust in the air or cross-contact,” Wong says. ”He attends university in Massachusetts, lives on-campus, and eats dorm food. He still carries an EpiPen but has so much more freedom than before his clinical trial. We will always be grateful.”