CALGARY -- A Calgary woman fighting stage 4 lung and brain cancer is asking for vaccination help as she waits for her second shot.
Shaun Buckwold received a Pfizer-BioNTech dose at the end of March. But while she anticipates her next jab, evidence is mounting that the immunocompromised are reporting less effective immunization results if the second dose isn't received within three weeks of the first.
Buckwold says extending the vaccination interval has left her scared and confused.
"I am just devastated," she told CTV News. "I would like some peace of mind to have a little bit of protection in what might be my last summer."
Buckwold is just one patient sounding the alarm after preliminary research from the U.K. was released.
That research says cancer patients are significantly less protected by a single dose of the Pfizer vaccine than the general public.
It also claims that an initial vaccination is less than 50 per cent effective in cancer patients if not followed by an additional dose within 21 days.
The research has not yet been peer-reviewed, but it's drawing increasing attention as Canada pushes back second shots.
In Alberta, the space between doses sits at 16 weeks.
"My doctor wants me to have (my next dose) on the 19th or the 20th (of April) because it's right between my treatments, (but) I can't get anywhere," Buckwold said.
"For cancer patients, this is not right. This is playing with fire."
Canadian Association of Pharmacy in Oncology (CAPhO) agrees.
“The study shows that three weeks after one dose of the vaccine an (antibody) response was found in 39 per cent of people with a solid cancer and just 13 per cent of people with blood cancer,” Tina Crosbie, president of CAPhO, said in a statement. “An antibody response was found in 97 per cent of the healthy volunteers tested.”
Cancer patients and other immunocompromised people are significantly more likely to experience severe outcomes or die if they contract COVID-19, making it more critical that they receive protection from the vaccine.
CAPhO is calling for the National Advisory Committee on Immunization (NACI) to specify in their recommendations that cancer patients receive their second dose on schedule, and no later than three weeks after the first dose.
In Alberta, that doesn't look likely in the near future.
When asked about the timeframes Sunday, a provincial spokesperson wrote to CTV News about federal delays in vaccine shipments.
"We are currently offering second doses within 16 weeks of the first dose to maximize the number of people getting a level of protection from an initial inoculation," Alberta Health's Sherene Khaw said. "We are awaiting a recommendation (regarding second doses for cancer patients) from the National Advisory Committee on Immunization and the Alberta Advisory Committee on Immunization. We will update Albertans as soon as any changes are made.
Buckwold says that's not good enough.
She's written and called her provincial representative multiple times and hasn't heard back.
"I am sick to my stomach over government policy playing with my life," she said.
U.K. researchers studied 151 cancer patients at three hospitals in the U.K. and 54 healthy control patients between Dec. 8, 2020 and Feb. 18.
Non-cancer patients had a markedly higher percentage of exhibiting an immune response three weeks after the first shot of the vaccine than cancer patients.
The timing of the second dose also had a significant impact on the percentage of cancer patients who mounted an antibody response.
The efficacy of the vaccine in solid cancer patients — patients with a physical tumour in one of their organs — at the five-week mark was 95 per cent in those who received their second dose 21 days after their first dose. These results are in line with the Pfizer phase 3 trials in the general population.
However, when solid cancer patients were assessed at the five week mark, only 43 per cent of those who had not received their second dose yet still showed an immune response in the form of antibodies.
Only eight per cent of those with a blood cancer and just one shot of the vaccine showed an immune response at five weeks.
