| Symvess, a Humacyte product, was approved by the Food and Drug Administration in December to help save limbs after severe trauma, whether it’s on the battlefield or in hospitals around the US. But Robert Lee, who spent 10 years at the FDA after a career as a vascular surgeon, told me in March that he repeatedly raised concerns with senior FDA leadership over Symvess, a long, thin white tube made of bioengineered tissue that surgeons can use to repair damaged blood vessels. Lee said the product’s failures can result in concerning rates of life-threatening bleeding — all while being no more effective than synthetic alternatives in use for decades. Since he came forward, others have voiced their concern. The codirectors of the Amy J. Reed Collaborative for Medical Device Safety at Northeastern University and Tufts Medical Center filed a petition April 10 asking the FDA to withdraw Symvess’s approval and hold a public meeting of outside experts to weigh its risks and benefits. “You’re talking about a threat to national health security,” Hooman Noorchashm, one of the codirectors of the collaborative, said in an interview. Humacyte Chief Executive Officer Laura Niklason said the petition is without merit. She also said Noorchashm had submitted nine different petitions over the years, none of which the FDA has agreed with as of yet. Yet Noorchashm has helped prevent the use of a dangerous device in the past. His collaborative is named after his late wife. Together, they led opposition to a gynecological device that harmed Reed before she died from a type of uterine cancer. As a result, the FDA warned a decade ago the device can spread cancer and shouldn’t be used “in the vast majority of women.” After Bloomberg’s article on Symvess ran, Lee wrote editors at JAMA Surgery calling into question a November paper published in the medical journal that analyzed Symvess clinical trial data but left out “serious outcomes,” including a concerning failure rate that led to dangerous bleeding. The paper, which was written by Niklason and several doctors, also reported better efficacy and amputation rates than FDA reviewers found after analyzing the data, Lee said. Discrepancies between the FDA’s and Humacyte’s take on the data are outlined in further detail in my article from last month. A spokesperson for Humacyte told me last week the FDA’s “very conservative approach” to the data is to blame for the differences between what was reported in JAMA Surgery and in FDA documents. Melina Kibbe, editor-in-chief of JAMA Surgery, said in an email that she spoke with Lee about his concerns with the November paper and that “this is being explored.” JAMA Surgery has also contacted the paper’s authors, Hannah Alani, a spokesperson for the journal told me last week. Humacyte says Lee has a conflict of interest because he formed a company that consults for dialysis companies, one of the next frontiers Humacyte hopes to sell its product in, though it does not yet have FDA approval. Lee says this isn’t a conflict of interest. He says his criticisms aren’t aimed at the company but at the FDA for not being more transparent and failing to hold a public meeting to air concerns with the device and hear expert opinions. Niklason said in an earnings call last month that “several of our surgeons who participated in our trauma trials were incensed” after Lee’s concerns were published. Three surgeons who were authors on the paper have publicly come to the defense of Symvess, which they say works well and is an important treatment addition. All of the hospitals where patients got Symvess as part of Humacyte’s clinical trials around the country are compensated for their work, a company spokesperson said, adding that this does not create a conflict of interest. One doctor Humacyte asked to speak out, Todd Rasmussen, a professor of surgery in the division of vascular and endovascular surgery at the Mayo Clinic, said his experience as part of a clinical trial of Symvess to treat narrow or blocked blood vessels in the leg showed that the product is safe and effective. He said it’s unfortunate disagreements within the FDA have impacted its rollout. “The people who are harmed are patients,” Rasmussen said. “To me the agency kind of needs to get its house in order and take care of these intra-agency disagreements.” That sums up this saga so far. I’ll be watching to see where this goes from here. — Anna Edney | 
