Editor's note: Find the latest COVID-19 news and guidance in Medscape's Coronavirus Resource Center.
Coronavirus vaccines have become a reality, as they are now being approved and authorized for use in a growing number of countries including the United States. The U.S. Food and Drug Administration has just issued emergency authorization for the use of the COVID-19 vaccine produced by Pfizer and BioNTech. Close behind is the vaccine developed by Moderna, which has also applied to the FDA for emergency authorization.
The efficacy of a two-dose administration of the vaccine has been pegged at 95.0%, and the FDA has said that the 95% credible interval for the vaccine efficacy was 90.3%-97.6%. But as with many initial clinical trials, whether for drugs or vaccines, not all populations were represented in the trial cohort, including individuals who are immunocompromised. At the current time, it is largely unknown how safe or effective the vaccine may be in this large population, many of whom are at high risk for serious COVID-19 complications.
At a special session held during the recent annual meeting of the American Society of Hematology, Anthony Fauci, MD, the nation's leading infectious disease expert, said that individuals with compromised immune systems, whether because of chemotherapy or a bone marrow transplant, should plan to be vaccinated when the opportunity arises.
In response to a question from ASH President Stephanie J. Lee, MD, of the Fred Hutchinson Cancer Center, Seattle, Fauci emphasized that, despite being excluded from clinical trials, this population should get vaccinated. "I think we should recommend that they get vaccinated," he said. "I mean, it is clear that, if you are on immunosuppressive agents, history tells us that you're not going to have as robust a response as if you had an intact immune system that was not being compromised. But some degree of immunity is better than no degree of immunity."
That does seem to be the consensus among experts who spoke in interviews: that as long as these are not live attenuated vaccines, they hold no specific risk to an immunocompromised patient, other than any factors specific to the individual that could be a contraindication.
"Patients, family members, friends, and work contacts should be encouraged to receive the vaccine," said William Stohl, MD, PhD, chief of the division of rheumatology at the University of Southern California, Los Angeles. "Clinicians should advise patients to obtain the vaccine sooner rather than later."
Kevin C. Wang, MD, PhD, of the department of dermatology at Stanford (Calif.) University, agreed. "I am 100% with Fauci. Everyone should get the vaccine, even if it may not be as effective," he said. "I would treat it exactly like the flu vaccines that we recommend folks get every year."
Wang noted that he couldn't think of any contraindications unless the immunosuppressed patients have a history of severe allergic reactions to prior vaccinations. "But I would even say patients with history of cancer, upon recommendation of their oncologists, are likely to be suitable candidates for the vaccine," he added. "I would say clinicians should approach counseling the same way they counsel patients for the flu vaccine, and as far as I know, there are no concerns for systemic drugs commonly used in dermatology patients."
However, guidance has not yet been issued from either the FDA or the Centers for Disease Control and Prevention regarding the use of the vaccine in immunocompromised individuals. Given the lack of data, the FDA has said that "it will be something that providers will need to consider on an individual basis," and that individuals should consult with physicians to weigh the potential benefits and potential risks.
The CDC's Advisory Committee on Immunization Practices has said that clinicians need more guidance on whether to use the vaccine in pregnant or breastfeeding women, the immunocompromised, or those who have a history of allergies. The CDC itself has not yet released its formal guidance on vaccine use.
Vaccines typically require years of research and testing before reaching the clinic, but this year researchers embarked on a global effort to develop safe and effective coronavirus vaccines in record time. Both the Pfizer/BioNTech and Moderna vaccines have only a few months of phase 3 clinical trial data, so much remains unknown about them, including their duration of effect and any long-term safety signals. In addition to excluding immunocompromised individuals, the clinical trials did not include children or pregnant women, so data are lacking for several population subgroups.
But these will not be the only vaccines available, as the pipeline is already becoming crowded. U.S. clinical trial data from a vaccine jointly being developed by Oxford-AstraZeneca, could potentially be ready, along with a request for FDA emergency use authorization, by late January 2021.
In addition, China and Russia have released vaccines, and there are currently 61 vaccines being investigated in clinical trials and at least 85 preclinical products under active investigation.
The vaccine candidates are using both conventional and novel mechanisms of action to elicit an immune response in patients. Conventional methods include attenuated inactivated (killed) virus and recombinant viral protein vaccines to develop immunity. Novel approaches include replication-deficient, adenovirus vector-based vaccines that contain the viral protein, and mRNA-based vaccines, such as the Pfizer and Moderna vaccines, that encode for a SARS-CoV-2 spike protein.
"The special vaccine concern for immunocompromised individuals is introduction of a live virus," Stohl said. "Neither the Moderna nor Pfizer vaccines are live viruses, so there should be no special contraindication for such individuals."
Live vaccine should be avoided in immunocompromised patients, and currently, live SARS-CoV-2 vaccines are only being developed in India and Turkey.
It is not unusual for vaccine trials to begin with cohorts that exclude participants with various health conditions, including those who are immunocompromised. These groups are generally then evaluated in phase 4 trials, or postmarketing surveillance. While the precise number of immunosuppressed adults in the United States is not known, the numbers are believed to be rising because of increased life expectancy among immunosuppressed adults as a result of advances in treatment and new and wider indications for therapies that can affect the immune system.
According to data from the 2013 National Health Interview Survey, an estimated 2.7% of U.S. adults are immunosuppressed. This population covers a broad array of health conditions and medical specialties; people living with inflammatory or autoimmune conditions, such as inflammatory rheumatic diseases (rheumatoid arthritis, axial spondyloarthritis, lupus); inflammatory bowel disease (Crohn's disease and ulcerative colitis); psoriasis; multiple sclerosis; organ transplant recipients; patients undergoing chemotherapy; and life-long immunosuppression attributable to HIV infection.
As the vaccines begin to roll out and become available, how should clinicians advise their patients, in the absence of any clinical trial data?
Risk vs. Benefit
Gilaad Kaplan, MD, MPH, a gastroenterologist and professor of medicine at the University of Calgary (Alta.), noted that the inflammatory bowel disease (IBD) community has dealt with tremendous anxiety during the pandemic because many are immunocompromised because of the medications they use to treat their disease.
"For example, many patients with IBD are on biologics like anti-TNF [tumor necrosis factor] therapies, which are also used in other immune-mediated inflammatory diseases such as rheumatoid arthritis," he said. "Understandably, individuals with IBD on immunosuppressive medications are concerned about the risk of severe complications due to COVID-19."
The entire IBD community, along with the world, celebrated the announcement that multiple vaccines are protective against SARS-CoV-2, he noted. "Vaccines offer the potential to reduce the spread of COVID-19, allowing society to revert back to normalcy," Kaplan said. "Moreover, for vulnerable populations, including those who are immunocompromised, vaccines offer the potential to directly protect them from the morbidity and mortality associated with COVID-19."
That said, even though the news of vaccines are extremely promising, some cautions must be raised regarding their use in immunocompromised populations, such as persons with IBD. "The current trials, to my knowledge, did not include immunocompromised individuals and thus, we can only extrapolate from what we know from other trials of different vaccines," he explained. "We know from prior vaccines studies that the immune response following vaccination is less robust in those who are immunocompromised as compared to a healthy control population."
Kaplan also pointed to recent reports of allergic reactions that have been reported in healthy individuals. "We don't know whether side effects, like allergic reactions, may be different in unstudied populations," he said. "Thus, the medical and scientific community should prioritize clinical studies of safety and effectiveness of COVID-19 vaccines in immunocompromised populations."
So, what does this mean for an individual with an immune-mediated inflammatory disease like Crohn's disease or ulcerative colitis who is immunocompromised? Kaplan explained that it is a balance between the potential harm of being infected with COVID-19 and the uncertainty of receiving a vaccine in an understudied population. For those who are highly susceptible to dying from COVID-19, such as an older adult with IBD, or someone who faces high exposure, such as a health care worker, the potential protection of the vaccine greatly outweighs the uncertainty.
"However, for individuals who are at otherwise lower risk – for example, young and able to work from home – then waiting a few extra months for postmarketing surveillance studies in immunocompromised populations may be a reasonable approach, as long as these individuals are taking great care to avoid infection," he said.
No Waiting Needed
Joel M. Gelfand, MD, MSCE, professor of dermatology and epidemiology at the University of Pennsylvania, Philadelphia, feels that the newly approved vaccine should be safe for most of his patients.
"Patients with psoriatic disease should get the mRNA-based COVID-19 vaccine as soon as possible based on eligibility as determined by the CDC and local public health officials," he said. "It is not a live vaccine, and therefore patients on biologics or other immune-modulating or immune-suppressing treatment can receive it."
However, the impact of psoriasis treatment on immune response to the mRNA-based vaccines is not known. Gelfand noted that, extrapolating from the vaccine literature, there is some evidence that methotrexate reduces response to the influenza vaccine. "However, the clinical significance of this finding is not clear," he said. "Since the mRNA vaccine needs to be taken twice, a few weeks apart, I do not recommend interrupting or delaying treatment for psoriatic disease while undergoing vaccination for COVID-19."
Given the reports of allergic reactions, he added that it is advisable for patients with a history of life-threatening allergic reactions such as anaphylaxis or who have been advised to carry an epinephrine autoinjector, to talk with their health care provider to determine if COVID-19 vaccination is medically appropriate.
The National Psoriasis Foundation has issued guidance on COVID-19, explained Steven R. Feldman, MD, PhD, professor of dermatology, pathology, and social sciences & health policy at Wake Forest University, Winston-Salem, N.C., who is also a member of the committee that is working on those guidelines and keeping them up to date. "We are in the process of updating the guidelines with information on COVID vaccines," he said.
He agreed that there are no contraindications for psoriasis patients to receive the vaccine, regardless of whether they are on immunosuppressive treatment, even though definitive data are lacking. "Fortunately, there's a lot of good data coming out of Italy that patients with psoriasis on biologics do not appear to be at increased risk of getting COVID or of having worse outcomes from COVID," he said.
Patients are going to ask about the vaccines, and when counseling them, clinicians should discuss the available data, the residual uncertainty, and patients' concerns should be considered, Feldman explained. "There may be some concern that steroids and cyclosporine would reduce the effectiveness of vaccines, but there is no concern that any of the drugs would cause increased risk from nonlive vaccines."
He added that there is evidence that "patients on biologics who receive nonlive vaccines do develop antibody responses and are immunized."
Even prior to making their announcement, the American College of Rheumatology had said that they would endorse the vaccine for all patients, explained rheumatologist Brett Smith, DO, from Blount Memorial Physicians Group and East Tennessee Children's Hospital, Alcoa. "The vaccine is safe for all patients, but the problem may be that it's not as effective," he said. "But we don't know that because it hasn't been tested."
With other vaccines, biologic medicines are held for 2 weeks before and afterwards, to get the best response. "But some patients don't want to stop the medication," Smith said. "They are afraid that their symptoms will return."
As for counseling patients as to whether they should receive this vaccine, he explained that he typically doesn't try to sway patients one way or another until they are really high risk. "When I counsel, it really depends on the individual situation. And for this vaccine, we have to be open to the fact that many people have already made up their mind."
There are a lot of questions regarding the vaccine. One is the short time frame of development. "Vaccines typically take 6-10 years to come on the market, and this one is now available after a 3-month study," Smith said. "Some have already decided that it's too new for them."
The process is also new, and patients need to understand that it doesn't contain an active virus and "you can't catch coronavirus from it."
Smith also explained that, because the vaccine may be less effective in a person using biologic therapies, there is currently no information available on repeat vaccination. "These are all unanswered questions," he said. "If the antibodies wane in a short time, can we be revaccinated and in what time frame? We just don't know that yet."
Philip D. Bonomi, MD, a professor of medical oncology at Rush Medical College, Chicago, explained that one way to ensure a more optimal response to the vaccine would be to wait until the patient has finished chemotherapy. "The vaccine can be offered at that time, and in the meantime, they can take other steps to avoid infection," he said. "If they are very immunosuppressed, it isn't worth trying to give the vaccine."
Cancer patients should be encouraged to stay as healthy as possible, and to wear masks and social distance. "It's a comprehensive approach. Eat healthy, avoid alcohol and tobacco, and exercise. [These things] will help boost the immune system," Bonomi said. "Family members should be encouraged to get vaccinated, which will help them avoid infection and exposing the patient."
Jim Boonyaratanakornkit, MD, PhD, an infectious disease specialist who cares for cancer patients at the Fred Hutchinson Cancer Research Center, agreed. "Giving a vaccine right after a transplant is a futile endeavor," he said. "We need to wait 6 months to have an immune response."
He pointed out there may be a continuing higher number of cases, with high levels peaking in Washington in February and March. "Close friends and family should be vaccinated if possible," he said, "which will help interrupt transmission."
The vaccines are using new platforms that are totally different, and there is no clear data as to how long the antibodies will persist. "We know that they last for at least 4 months," said Boonyaratanakornkit. "We don't know what level of antibody will protect them from COVID-19 infection. Current studies are being conducted, but we don't have that information for anyone yet."
This article originally appeared on MDedge.com, part of the Medscape Professional Network.
Medscape Medical News © 2020 WebMD, LLC
Cite this: COVID-19 Vaccines: Safe for Immunocompromised Patients? - Medscape - Dec 17, 2020.