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cancer patients worry over wait for second covid shot

experts say that delaying the second dose could be catastrophic for those with compromised immune systems.

by vanessa hrvatin

apr 21 2021

5 minute read

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cancer patients worry over wait for second covid-19 shot

advocates are hoping cancer patients won't have to wait to get their second shot of the covid-19 vaccine. getty

advocates across the country are calling on provincial governments to adjust covid-19 vaccine prioritization so cancer patients receive their second dose within four weeks rather than waiting up to 16 weeks.

concern over a delayed second dose comes from preliminary data out of the u.k. which found people with solid cancers (a physical tumour) and blood cancers had a much lower antibody response following just one dose of the pfizer vaccine compared to healthy people. when a second booster was given 21 days later, nearly all solid cancer patients had a much higher antibody response. this means delaying a second dose could prevent patients from having a fuller response to the vaccine and leaves them susceptible to covid-19 while they wait for their second jab.

in march, the national advisory committee on immunization (naci) recommended extending dose intervals to 16 weeks so more canadians could receive their first shot. to date, the committee has not suggested any exemptions to this recommendation for immuno-compromised people, but it’s ultimately up to each province to make decisions about vaccination priority. on march 26, ontario introduced exceptions, stating that transplant patients and cancer patients actively on certain treatments should receive the second dose on label — which is 21 days for pfizer and 28 days for moderna.

but advocates say the guidelines aren’t clear and many patients in ontario are still waiting many weeks, sometimes months for their second dose.

“when ontario came out with these guidelines, no one on the ground knew what they were, and patients were going to their appointments for their first vaccine and were still getting booked [for their second dose] four months later,” says martine elias, executive director of myeloma canada. “now what we’re seeing is that the hospitals are providing recommendations to patients about the second dose, but it’s not happening everywhere, it really depends on where you live.”

according to the ontario guidelines, not everyone with cancer is eligible to receive their second dose on time — it is limited to people undergoing chemotherapy, targeted therapies and immunotherapy, and doesn’t include people receiving hormonal or radiation therapy or those in remission. these groups are most vulnerable, as certain treatments lower the immune system and require patients to access the health care system often, increasing chances of exposure. but this also introduces grey zones, such as patients with blood cancer who haven’t started treatment yet, but have a low immune response just by nature of their disease.

at princess margaret cancer centre in toronto, much of the focus has been on trying to help patients navigate these exemptions. doctors are writing letters for patients to bring to vaccination appointments, confirming they meet criteria for on-label delivery of their second dose.

“this is a very stressful time for the patients because they’re sick and on top of it they have to navigate a system that has become very complex,” says dr. monika krzyzanowska, chair of the covid steering committee at princess margaret cancer centre.

while the second dose exemption remains murky in ontario, none of the other provinces have introduced such an exemption. healthing.ca reached out to several health authorities and each said the primary goal for the time being is providing first doses to as many people as possible.

and according to dr. fiona smaill, this isn’t unreasonable.

“when you look at how we are going to protect our cancer patients from covid-19 infection, vaccination is one tiny part of it,” says smaill, professor of infectious diseases and microbiology at mcmaster university. “reducing community transmission is probably going to be a much bigger component of protecting an individual rather than a vaccine given to an individual person. even with two doses of vaccine that person is still going to have to be very careful until we get community transmission down.”

lack of evidence is also a challenge — this is a relatively data-free zone since immuno-compromised people were left out of vaccine clinical trials. but dr. ilan schwartz says limited data doesn’t mean immuno-compromised patients should have to wait, especially considering that this cohort typically has the most severe covid-19 outcomes.

“the schedules that were used in [the vaccine clinical] trials are what forms the bulk of our evidence for the efficacy of when these vaccines work best,” says schwartz, an infectious disease physician who has been advocating for the alberta government to bump up the timing of second doses in people who are immuno-compromised. “looking at the balance of risks and benefits, it would be imperative for people who are immuno-compromised to get their booster shot as early as the evidence would support, which is three to four weeks depending on the specific vaccine.”

as canadians endure the third wave of the pandemic, there is no better time to prioritize fully vaccinating vulnerable groups according to dr. brian koffman, chief medical officer of the chronic lymphocytic leukemia (cll) society.

“making these patients wait more than three or four prescribed weeks is exposing them for another couple of months, and with the pandemic raging in certain parts of canada — right now that could be catastrophic,” says koffman. “we’re not trying to prevent people from getting covid, we’re trying to prevent people from getting severe covid. if that is our goal then the first people on the list should be the elderly, the immuno-compromised and the nursing home patients because these are the people who are very high-risk, and we should get them the full dosage of the vaccine to protect them.”

with policies and recommendations constantly evolving, many cancer patients and organizations across canada continue to advocate for a second dose on label.

“cancer patients have been so compliant in the last year by staying home and following the directions of public health and now they’re being told they aren’t going to be looked after the way they should — that’s how they’re interpreting this situation,” says myeloma canada executive director martine elias.

“it’s not fair that these patients can’t get the right care.”

vanessa hrvatin is a writer with healthing.ca.

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cancer patients worry over wait for second covid shot

experts say that delaying the second dose could be catastrophic for those with compromised immune systems.

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cancer patients worry over wait for second covid shot

experts say that delaying the second dose could be catastrophic for those with compromised immune systems.

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