December 7, 2021
In early 2019, Daniel Grosu found himself dealing with compounding personal crises: he had relocated his parents, who were both recently diagnosed with cancer, from Arizona so they could receive care at the University of California, San Diego (UCSD). Then, in April, his beloved dog, Poppy, received an equally devastating diagnosis: she had advanced pancreatic cancer. Poppy, an 8-pound, mixed-breed rescue, had a long life ahead of her—she was only four. But her disease progressed quickly. Poppy was in so much pain in the wee hours of May 24, 2019, that Grosu had to rush her to the emergency room to put her to sleep.
Grosu, who was Illumina’s first chief medical officer in the early 2010s, knew what tests were available on the market for cancer treatment selection. His parents both had their tumors sequenced for this purpose. So, when Poppy was diagnosed, Grosu aimed to employ a similar strategy. He wondered if there was a way to sequence her tumor to find targeted treatments. But he came up empty. “I found out very quickly that this entire field of precision oncology had not yet intersected the world of veterinary medicine,” he says.
The lack of genomics resources in this space then inspired Grosu to launch PetDx, a molecular diagnostics company for pets.
Being able to take a molecular deep dive into a dog’s DNA for clues of disease is especially important since dogs can’t verbalize symptoms in the same way humans can—not to mention that they are generally very good at suppressing signs of pain. It’s only when dogs exhibit clinical signs—if they’re hunched over in pain, throwing up blood, losing weight, or no longer excited by the prospect of a walk—that they’re typically brought to the vet. By then, says Grosu, it is often too late, as they already have advanced disease. “That’s all the more reason to find a way to diagnose cancer earlier,” he says. “As in humans, early diagnosis can lead to improved outcomes and even to a cure.”
As Grosu researched the prospects of this venture, he discovered that cancer is by far the single biggest killer in dogs. In fact, our canine friends are ten times more likely to be diagnosed with cancer than humans in a given year: out of 90 million pet dogs in the US, six million new cancer diagnoses are reported every year, whereas there are fewer than 2 million new cancer diagnoses per year in over 330 million people in the US.
As an alumnus of Illumina, Grosu knew that the company’s gene sequencing technology could be leveraged for earlier detection of cancer from blood samples. PetDx, based in San Diego, is currently using the Illumina NovaSeq™ 6000 for all its sequencing needs. The lab instruments at PetDx’s offices are all labeled after their employees’ dogs; the NovaSeq in the lab is colloquially referred to as PoppySeq.
PetDx has validated the clinical performance of their multi-cancer early detection (MCED) liquid biopsy test, called OncoK9®, on samples from over 1,000 dogs collected at over 40 veterinary clinics around the world. Their clinical validation study, known as the CANDiD (CANcer Detection in Dogs) Study, demonstrated the test’s ability to detect cancer-associated genomic alterations in 30 different canine cancer types.
The company has partnered with veterinary clinics across the country, including many in Southern California, to bring this novel type of testing to families. Pet owners can have their dogs screened for cancer during the annual wellness visit, or the vet might order the test if cancer is suspected on clinical grounds. Veterinarians can simply collect the blood sample and send it to PetDx’s central lab in UCSD’s Science Research Park for processing. Within two weeks, PetDx will send back a report indicating whether or not a cancer signal has been detected in the sample, and recommend next steps for pursuing a definitive diagnosis.
Grosu envisions a future where PetDx may become the leading veterinary cancer diagnostics company by “unleashing the power of genomics to improve pet health.”
“People really care about their pets, and we can help make a big impact in the lives of many families,” says Grosu. “Because when a pet has cancer, it’s not just the pet that’s suffering. It’s really the entire family that’s suffering.”