One day in July, Tess Pettavino, chief executive of the charity that organizes Only Watch — a biennial fund-raising auction that in 2021 had a wristwatch sell for $33.6 million, a world record — was working in a home office high above Monaco’s harbor and its ranks of superyachts.

Just days earlier she had appeared in a video that, along with news releases and social media posts, outlined the plans for Only Watch 2023, scheduled for Nov. 5 in Geneva. Watch news outlets such as Hodinkee, Fratello and Revolution were writing about the 66 one-of-a-kind timepieces that had been donated to the biennial event by companies including Bulgari, F.P Journe, Audemars Piguet and Tudor.

But few included more than a mention of the reason for the auction: funding research on Duchenne muscular dystrophy (D.M.D.), a genetic disease that primarily affects boys, appearing in about one in every 3,500. Children with D.M.D. gradually lose control of their muscles, and cardiac complications eventually lead to death.

It was the disease that killed Ms. Pettavino’s younger brother, Paul, in 2016, when he was 20.

Ms. Pettavino, 29, rarely talks of Paul. But, “I don’t feel it was a sad vibe,” she said of her brother’s life with the disease. “It kind of pushed us as a family to be super resilient.”

And on this particular day, she was describing a drug developed over the past decade by SQY Therapeutics, one of the two biotechnology companies established with the charity’s funds.

The research so far, she said, has been supported by $40 million of the more than $110 million that Only Watch and a few individual donors have raised since the auction’s debut in 2005. (SQY Therapeutics, based in St.-Quentin-en-Yvelines, France, also has received a little more than $2 million from the French government.) The plan is to spend conservatively, so that the money lasts to meet research and development needs over the long term, she said.

“SQY51 is a super promising lead,” Ms. Pettavino said, adding that the first phase of the clinical trials of the drug, whose name is pronounced Sky51, began in June. “To halt the disease is the goal, and potentially also to regain a little bit of physical capacity.”

The first phase involves a six-month trial; if successful, the drug then would have another six-month test.

“Maybe this is something,” she said, “but we are very careful in the way we raise hopes,” stressing it was the organization’s first trial of a drug it had developed. (Some of the more than 50 researchers it supported over the years also have conducted clinical trials.)

‘To Do Good’

Paul Pettavino was diagnosed with D.M.D. in 2000, when he was 4 years old.

The following year, Luc Pettavino, Tess and Paul’s father and chief executive of the Monaco Yacht Show at the time, established the charitable foundation Association Monégasque contre les Myopathies, (in English, Monegasque Association Against Myopathies). Myopathies are disorders primarily affecting the skeletal muscle structure or metabolism.

“I did not want to be perceived as the father of Paul, a victim of a disease — something sad. ‘Please help us because those children are dying.’ I could not occupy such a space, it would be too heavy emotionally for me,” said Mr. Pettavino, now 59. “ I just wanted to put our sights towards something that was a therapy and positive and joyful and creating beauty to do good.”

He began with charity art sales, but then envisioned an auction every two years that would feature watches made exclusively for the event. He reached out to watch industry leaders like Nicolas Hayek Sr. of Swatch Group; Jean-Claude Biver, then at Blancpain; the Scheufele family of Chopard; the Stern family of Patek Philippe and the Swiss auction house Antiquorum — and they all agreed to participate.

“Only Watch is a group effort that was always based on a friendship vibe with good energy. It is a platform of trust, simplicity and creativity,” Mr. Pettavino said.

The number of brands has nearly doubled since that first event, and large auction houses with watch departments take turns staging the sale free of charge. This year Christie’s will be handling the hammer; in 2021, it was Phillips. (That was when a Patek Philippe Grandmaster Chime, the house’s most complicated wristwatch, was offered in a unique stainless steel model — trumpeted by “The Only One” label on the dial — and two bidders pushed each other to a $33.6 million hammer price, a record that still stands. “It was the decision of two bidders not to let go for the beauty of the piece,” Mr. Pettavino said. “We know the bidders; they really like the cause too.”)

The auction’s patron, Prince Albert II of Monaco, has attended all nine Only Watch auctions.

Even though he admits he is “not really” a watch collector, the prince, interviewed in his palace office crammed with books and memorabilia from around the world, said he had “bought several watches at the auctions. Some of them I still have; others I have gifted.” Afterward, he posed with Mr. and Ms. Pettavino for photographs.

The Pettavinos have “transformed a personal history into hope for many,” the prince wrote in an earlier email, also mentioning the role that his mother, Princess Grace, had taken on in her involvement with the Monaco Red Cross.

“To see a chief of state so sincerely committed — which is really the case — is a very important component for us,” Ms. Pettavino said after the palace meeting. “He is not just a name on top of a poster or catalog.”

No Limits

While Mr. Pettavino continues to be the driving force behind the auction itself, reaching out to watchmakers and collectors on its behalf, Ms. Pettavino took over her father’s role as the association’s chief executive in September 2022 (five years after she earned a double master’s degree in corporate and public management in a program operated jointly by the HEC Business School and the Paris Institute of Political Studies, known as Sciences Po).

In its 22 years of existence, the association has financed the establishment of two biotechnology companies — SQY Therapeutics and Synthena, based in Bern, Switzerland — whose executives and board members are composed of representatives of Association Monégasque contre les Myopathies, researchers, and parents of D.M.D. patients. The main reason for financing such companies, Ms. Pettavino said, was to ensure that no time limits or profit requirements were placed on promising research.

“If you were to have a business mind-set with R&D funds you would be given two to three years to proof of concept,” a term for the early stages of testing, she said. “We are saying our only goal is to get there.

“Scientists need game-changing structural means to make that kind of progress and that’s what we have given them, with no other expectations than that we believe in you.”

(While the cost of SQY51 would rise significantly if its development continues, it still is likely that its total cost would be far less than $1.3 billion, the average cost of bringing a new drug to market, according to a 2020 study in the Journal of the American Medical Association.)

Cautious Optimism

D.M.D. occurs when the dystrophin gene has a flawed section, rendering the mRNA — DNA’s messenger — unable to produce dystrophin, a protein necessary for stabilizing and protecting muscle fibers linked to the skeleton and heart.

SQY51, the drug now being tested on 12 French boys with the disease, introduces a molecule that piggybacks on the mRNA and makes the flawed section readable again, enabling the production of dystrophin. The effect is called exon skipping.

In the current trials, “several aspects suggest that the efficacy is higher than previous trials,” Dr. Karim Wahbi said. “But we must be very careful.” (He has been involved in all aspects of the preclinical and clinical work.)

“If SQY51 works, it would work for about 15 percent of D.M.D. patients,” he said, adding that the technology might be adaptable. “It would take years, but in the end approximately 50 percent of D.M.D. patients would potentially be treatable with exon skipping.”

Dr. Wahbi, who is head of the reference center for neuromuscular cardiomyopathies at Cochin Hospital in Paris and a professor of cardiology at Paris Cité University, also linked watchmaking and science. “One must be very rigorous at each step of the process, from the idea to a final project,” he said. “As a scientist I am interested in the innovations behind watchmaking; the ability to give accurate measurement of time with a mechanical process really fascinates me.”

Some large pharmaceutical companies, like BioMarin in Novato, Calif., and Sarepta Therapeutics in Cambridge, Mass., in collaboration with the Swiss giant Roche, have independently reached clinical trials on their approaches to D.M.D. drugs. But no one, at least so far, has been able to halt the development of the disease in humans.

“There are concepts similar to ours, treatments have been developed,” said Dr. Helge Amthor, who is leading the SQY51 trial and also is a professor of pediatric neurology at University Paris-Saclay. “However, not sufficiently efficient to really change the disease course.”

Dr. Amthor is also very cautious, but talked of “promising, principal proof” that the molecules developed for SQY51 are more efficient than those previously found. “And if — I say if — it works will be a medical revolution. It will be like antibiotics in the 1950s.”

Luis García, director of the laboratory team at the University of Versailles St.-Quentin-en-Yvelines in Versailles, France, where the chemistry behind SQY51 was developed, is equally optimistic. “If it works — in one year, maybe sooner, we will know if it works — this could be a toolbox translatable to many diseases. Maybe even cancer,” he said.

World Tour

Monaco’s authorities have oversight of the charitable organizations based in the principality, but there are no requirements for the groups to submit or to publish audited financial reports. In the case of the association, Ms. Pettavino said, all of the basic financial information can be found on its website, onlyproject.org.

According to onlyproject.org, the charity’s running costs are around 1 percent of the auctions’ proceeds, a proportion that Ms. Pettavino said was possible because there are only two full-time employees: herself and Alice Dupont, an event manager in Monaco. And they both work from home, with Ms. Pettavino dividing her time between Monaco and Paris.

The Pettavinos say their strategy has always been to be conservative with spending. “It is our responsibility to make sure that means is not a problem,” Ms. Pettavino said, noting funds are needed for continuing projects as well as new and future research.

As plans proceed for the 10th edition of Only Watch in Geneva in November, the timepieces are being sent on a world tour, which started in Los Angeles last week and continues Sept. 14-17 at Christie’s at Rockefeller Plaza in New York City, followed by stops in Monaco, Hong Kong, Bangkok, Singapore, Geneva and Dubai, United Arab Emirates.

The participating brands range alphabetically from Andersen Genève to Zenith — and the mechanical level of the timepieces ranges from time-only to super-complex minute repeaters that, thanks to miniature gongs, chime the time on demand. Visually, most are heavily adorned with métiers d’art techniques including guilloché or machine-aided engraving; miniature painting; mosaics; gem setting and marquetry.

“Each edition seems to surprise all of us with the level of the game that is rising — not by steps, but by floors in one go,” Mr. Pettavino said.