Federal Judge Signals Fraud Claims Against Cancer Filter Firm ExThera May Advance

A San Francisco federal judge indicated she may allow additional claims against ExThera Medical, whose ONCObind blood filter was marketed as a cancer cure for $45,000 a round.

Judge Eyes Expanded Liability for ExThera Medical Over $45,000 Cancer Filter Treatment

A federal judge in San Francisco signaled Friday that she would allow additional claims to move forward against ExThera Medical Corporation, a Bay Area medical device company that marketed its blood filtration technology as a potential cure for metastatic cancer — but she stopped short of issuing any formal ruling.

"This is a case where people were told this is a new procedure that could really save you from what is going on here; they tried it, it was painful, it didn't work, it maybe killed them. That will be a triable issue," said U.S. District Judge Maxine M. Chesney.

Courthouse News Service reports that Chesney, a Clinton appointee, said she was leaning toward the plaintiffs on the question of whether ExThera should be held liable for statements made by former board member John Preston in a promotional video hosted on the company's website. In the video, Preston is identified as "Director, ExThera Medical" and makes several claims about the company's "ONCObind" filter — including that four hours on the device is "the difference between life and death."

"It seems to me like he's given the authority to speak on behalf of ExThera," Chesney said, describing Preston as something of a company spokesperson.

The judge also signaled that plaintiffs had sufficiently addressed earlier deficiencies in their negligence and wrongful death claims. Their first amended complaint added a line stating: "Doctors will attest that ExThera's actions directly caused these plaintiffs' deaths." Chesney noted that while lay plaintiffs cannot make that assertion themselves, qualified medical professionals can.

However, Chesney was less persuaded on other points. She questioned whether ExThera could reasonably have anticipated that two wives of cancer patients receiving ONCObind treatment would relay alleged misrepresentations — made by Preston and Dr. Sanja Ilic, ExThera's chief regulatory officer and vice president of clinical, regulatory and medical affairs — to a third patient's spouse in a "cancer wives" support group.

"There is no real showing here that Ilic knew Ms. Hudlow or Ms. Baskin were going to convey specific statements to Ms. Bowen. That didn't really quite add up to me," Chesney said.

The judge also expressed doubt over claims tied to certain sections of ExThera's website, questioning whether each plaintiff had actually visited those pages.

"The issue is if the plaintiffs pleaded that they saw these things. If they actually did see the banner, and they did go to the FAQ page, I think they really need to say that," she said.

Chesney gave no indication of when a written ruling would be released.

Annie Wanless of Lieff Cabraser Heimann & Bernstein, representing the plaintiffs, said in a statement to Courthouse News that they are hopeful the court will allow the claims to proceed to discovery and trial. "We are grateful for the court's time and attention to this matter," Wanless added. A representative for ExThera did not respond to a request for comment.

Plaintiffs filed suit against ExThera in March 2025, alleging the company falsely marketed ONCObind as a "medical miracle" capable of curing metastatic cancer. ExThera's Seraph 100 blood filters initially drew attention as a potential treatment for Covid-19 during the pandemic. The company later pivoted, claiming the technology could remove circulating tumor cells from the bloodstream. It began offering ONCObind treatments at a clinic on the Caribbean island of Antigua at $45,000 per round.

At least three patients died within days or weeks of leaving Antigua after undergoing treatment, the plaintiffs allege, while many others saw their conditions worsen and their cancer markers rise.

In May, Chesney dismissed civil RICO, civil RICO conspiracy, negligence, battery and wrongful death claims, while allowing fraud, intentional infliction of emotional distress and product liability claims to proceed. The judge also dismissed most defendants from the case at that time — among them billionaire investor Alan Quasha; his private equity firm Quadrant Management, which had invested in ExThera; and Quadrant Clinical Care, the Antigua-based clinic that administered the procedure.

Also dismissed were Dr. Devon Quasha, the billionaire's daughter and former chief medical officer of Quadrant Clinical Care, and Preston, who the plaintiffs say spoke to them directly about the treatment's "miraculous results."

Friday's hearing addressed whether further claims in the amended complaint could survive.

Source: Courthouse News Service