Immunocompromised people were excluded from the trials. That said, there is a very long history of vaccine use in immunocompromised individuals. Live, attenuated vaccines have in some cases caused problems for immunocompromised recipients, but not “killed” or inactivated vaccines, like the adenovirus vector COVID vaccines. The Pfizer and Moderna COVID vaccines don’t even contain dead virus of any sort, but instead only some viral RNA. Thus, as expected, they are associated only with the typical (nearly always mild) side effects of any vaccine, none of which will likely be enhanced in an immunocompromised patient. There is thus no reason to think immunocompromised patients have any enhanced safety risk from the mRNA or adenovirus vector COVID vaccines.
Efficacy, or course, is another matter. That will depend on each person’s immune system. This is why cancer patients and others with immunocompromise should consult with their doctors about taking the COVID vaccine. My opinion is that the vaccines will still be a good choice for most people, including immunocompromised people, because the alternative—getting, or at least high risk of getting, COVID—is quite bad, especially for an immunicompromised person. Remember that if there is seroconversion, even a lesser response may well protect against the worst outcomes (severe disease and death). In my view, the main reason to talk to your doctor about the vaccine if you are immunocompromised is to determine whether you should get your antibody titer tested after taking it, and/or whether you should continue to observe restrictions on your activities and contacts despite taking it, due to efficacy worries.
In any case, I will take the strongest possible vaccine I can get as early as I can get it.
7/19: Rectal cancer: Initially staged as IIIA, T2N1M0
Initially approx 4.25 cm, low/mid rectum, mod. well diff. adenocarcinoma
8/22 -10/14 4 rounds FOLFOX neoadjuvant, 3 w/Oxiplatin (lots of side effects/reduced size est. 70-75%)
Switched to neoadjuvant chemorad in 11/19 (Xeloda and approx. IMRT, 60 Gy, 33 fractions)
Trying to achieve cCR.