At a Glance
- Kevin Heyink, a Lynch syndrome carrier, joined a Houston vaccine trial that reduced his precancerous lesions.
- The vaccine trained his immune system to target Lynch-specific proteins.
- After the trial, his colonoscopies showed no polyps for the first time in 20 years.
Why it matters: The trial offers a potential preventive strategy for millions of Lynch carriers worldwide.
Kevin Heyink’s fight against cancer began long before he entered a clinical trial. After losing his father, brother, and several relatives to various cancers in their 30s and 40s, he discovered he carried the same genetic mutation that had doomed his family.
Lynch Syndrome: A Family Legacy
Heyink’s father, who died in 2009, identified his carrier status after a family health review. The mutation, known as Lynch syndrome, 80% increases the risk of colorectal cancer before age 50 and also raises the likelihood of endometrial, ovarian, gastric, bowel, and some brain cancers.
Since age 20, Heyink has undergone an annual colonoscopy and an endoscopy every other year. In his 30s, the procedures often revealed precancerous growths-polyps or adenomas-that required removal. The physical demands were clear, but he also described a persistent mental strain: “There is a certain level of mental stress that it takes,” he told TODAY.com. “As I get older, and now that my brothers have had cancer, it’s quite anxiety-provoking.”
He explained the condition to his four children, framing it as a spiritual challenge: “It’s something they can bring to God in prayer.” Yet he knows what it feels like to live in constant vigilance.
A New Preventive Vaccine
In January 2023, Heyink traveled to Houston to join a phase-1b/2 trial of a preventive cancer vaccine developed by Nouscom. The vaccine uses a modified, inactive adenovirus-not mRNA-to train the immune system to recognize proteins produced by Lynch carriers.
Dr. Eduardo Vilar Sanchez, one of the trial’s leads and a professor at the University of Texas MD Anderson Cancer Center, explained the science: The mismatch repair system that corrects DNA errors is defective in Lynch carriers. This defect creates unique proteins that can trigger cancer. The vaccine exposes the body to a harmless version of these proteins, prompting an immune response that could eliminate future cancerous or precancerous cells.
Unlike therapeutic cancer vaccines that aim to treat existing tumors, this one is purely preventive. If a vaccinated carrier later develops abnormal cells, the immune system is already primed to attack them.
How the Vaccine Works
- Targeted proteins: Proteins unique to Lynch syndrome carriers.
- Adenovirus vector: Delivers the protein blueprint safely.
- Immune training: Encourages T-cells to recognize and destroy cells expressing the target proteins.
- Long-term response: Immune markers persisted for at least a year after vaccination.
The Trial and Its Results
Heyink is one of 45 Lynch carriers in the trial, all of whom were healthy at enrollment. Colonoscopies before and after the trial confirmed no signs of cancer.
The trial’s results were published in Nature Medicine. Key findings include:
| Metric | Before | After | Difference |
|---|---|---|---|
| Precancerous lesions | 4 per colonoscopy | 1 per colonoscopy | 75% reduction |
| Advanced cancers | 0 | 0 | None observed |
| Immune response | N/A | Sustained for 12 months | Positive |
In August 2023, Heyink’s routine screening returned clear: “For the first time in 20 years, it came back perfectly clear,” he said. Two subsequent colonoscopies also showed no precancerous growths-“three in a row that have come back without any pre-cancerous growths, which is just incredible.”
The vaccine’s side effects were mild and comparable to a COVID-19 shot: redness, soreness, low-grade fever, and fatigue. After his first dose, Heyink felt exhausted and feverish the next day, but subsequent doses in January and May 2024 produced no noticeable side effects.
Personal Impact and Future Hope
Heyink views his participation as a way to pay forward the discovery his father made about Lynch syndrome in their family. He says, “I attribute all of this to the work of God. He’s led me on this path, he’s given me this opportunity.” He also acknowledges the anxiety that a Lynch diagnosis can cause but sees the trial as “hope on the horizon.”
Dr. Sanchez added that while more trials are needed for broader approval, the current results are “a message of hope that things are moving forward.” He praised the enthusiasm of participants: “The energy of the participants in this clinical trial was so refreshing.”
Heyink hopes the vaccine will become available for his children, nieces, and nephews, giving them a chance to avoid the cancer risk that has plagued his family.
Key Takeaways
- Kevin Heyink is a Lynch syndrome carrier who has lived with constant cancer surveillance.
- A new vaccine trained his immune system to target Lynch-specific proteins.
- Trial results show a significant reduction in precancerous lesions and no advanced cancers.
- The vaccine’s side effects were mild, and immune responses lasted at least a year.
- Heyink’s story illustrates the potential of preventive vaccines for high-risk genetic conditions.
This story first appeared on TODAY.com.
