Vaccinations for Patients with CLL / SLL (Revised June 25, 2026)          

Polio Vaccine

• The scourge of polio has resurfaced in some communities in the United States most likely due to low vaccination rates. The only polio vaccine that has been available in the USA since the year 2000, is the inactivated injected vaccine, or IPV, though many other countries still use a recently updated live attenuated (weakened) oral polio vaccine. Again, CLL / SLL patients should avoid any live vaccines. If you were not vaccinated as a child, which would be most unusual, it would be good to discuss the primary inactivated series with your healthcare team. If you were vaccinated, but travel to, live in or work in a high-risk area, it may be appropriate to discuss with your doctor whether a booster with IPV makes sense.

RSV

Respiratory Syncytial Virus (RSV)

• RSV is an exceedingly common pathogen that causes a respiratory tract infection ranging from the nose to the lungs. Illness can range from symptoms of a mild cold with nasal congestion and drainage to life threatening pneumonia and death. Those at most risk are children, the elderly and high risk individuals with underlying illnesses including immunocompromise, cardiopulmonary disease, renal dysfunction and diabetes amongst others. It has been estimated to cause approximately 159,000 hospitalizations and 10,000 deaths among adults ages ≥ 65 years in the US annually. Like influenza, RSV has a seasonal pattern from October to March with a peak in December with vaccine timing ideally in late summer or early fall before community spread circulation starts to rise. There is no available treatment except for supportive measures and prevention with vaccination is the best option available.
• The three FDA approved RSV vaccines are:

1. 1. Abrysvo (RSVPreF): FDA approved for adults ages ≥ 60 years, and adults ages 18-59 years at high risk, and pregnant women at 32-36 weeks gestation.
   2. Arexvy (RSVPreF3): FDA approved for adults ages ≥ 60 years, and adults 18-59 years at increased risk.
   3. mRESVIA (mRNA-1345): approved for adults ages ≥ 60 years, and younger adults ages 18-59 years at increased risk.

• The CDC recommends a single RSV vaccine for all adults ages ≥ 75 years and adults ages 50-74 years at increased risk for severe RSV, including those with moderate to severe immunocompromise. In contrast, IDSA guidance is broader for immunocompromised patients, recommending RSV vaccination for all adults ≥ 18 years with immunocompromise.
• At present, the RSV immunization is not recommended as an annual vaccine and is only to be given as a single dose.
• In the FDA approval trials efficacy against lower tract infection within the first season of use ranged from 63%-82% in immunocompetent adults. Two subsequent U.S. studies in immunocompromised adults ages ≥ 60 years found the RSV vaccine based upon a pooled vaccine efficacy rate to be 70% effective against RSV-associated hospitalization in immunocompromised adults. ( 2024;404:1547–1559 And JAMA Network Open. 2025;8(5)e258322.

• In terms of adverse events, significant side effects were not increased in the vaccinated vs. non-vaccinated individuals during the FDA trials with the exception of Guillain-Barré syndrome (GBS) being reported for Abrysvo and Arexvy. Following FDA approval, a post-marketing observational study using Medicare claims data suggested an estimated 9 excess cases of GBS per million doses of Abrysvo and 7 excess cases of GBS per million doses of Arexvy. Based on risk-benefit analysis, the benefit in preventing hospitalization and death is believed to far outweigh the risk of vaccination.

Shingles Vaccine

• Varicella-zoster is a viral infection that is spread through respiratory droplets causing a primary infection known as chickenpox, an itchy rash that progresses from red bumps to fluid filled vesicles, often associated with fever and fatigue. Following resolution of infectious symptoms and signs, the virus does not clear from the body, but instead lies dormant hidden in nerve cells. At a later time, often with advancing age and weakened immunity, the virus may reactivate in a form known as herpes zoster affecting one in three persons over the course of their lifetime. The illness most commonly presents as a painful blistering skin rash known as shingles. However, herpes-zoster may reactivate in the eye, nerves of the face, brain or spinal cord resulting in various complications including vision loss, facial paralysis, long term mental decline, paralysis, and death. Furthermore, up to 10-18% of individuals who experience shingles may develop persistent pain in the area where the rash has resolved known as postherpetic neuralgia.
• The first vaccine developed to prevent herpes-zoster infection was Zostavax which has been discontinued globally as of 2024.
• Shingrix, the currently available vaccine, has been shown to reduce reactivation of the virus in the skin, eye, cranial nerves and central nervous system. In the immunocompetent adult, vaccine efficacy for the prevention of shingles is about 97% for adults ages 50-69 and 91% for adults > 70 years of age. For prevention of postherpetic neuralgia, efficacy is about 91% for adults ages ≥ 50 years and 89% for adults ages ≥ 70 years. For patients with CLL / SLL, the immune response to the vaccine is not as robust, and unfortunately, exact efficacy data for prevention of disease is not available. However, a clinical study in CLL / SLL patients has shown an immune response in both the humoral and cellular pathways to the vaccine in both treatment naïve individuals and those on Bruton tyrosine kinase (BTK) inhibitors though in the latter group there was a lesser effect. (Blood Advances. 2022;6(6):1732–1740.)
• The CDC recommends Shingrix for adults ages ≥ 50 years and immunocompromised adults ages ≥ 19 years.
• Vaccination is recommended for all CLL / SLL patients and if possible before the start of treatment, however, vaccination should not be delayed if on a BTK inhibitor. Timing of vaccination might need to be adjusted or delayed if receiving anti-CD20 antibody treatment and should be discussed with your physician.
• Vaccination is a 2 dose series. The initial dose is followed by a second dose 2-6 months later. However, the interval between the first and second dose may be reduced to 1-2 months if necessary before stronger immunosuppressive therapy is administered.
• Revaccinate with Shingrix if you previously received the Zostavax due to the waning protection from that initial vaccine.
• Proceed with the Shingrix vaccine if you are on antiviral prophylaxis such as acyclovir or valacyclovir as these will not reduce the efficacy of the vaccine.
• If you experience herpes-zoster and have not previously been vaccinated with Shingrix, proceed with vaccination once the acute illness has resolved.

Tetanus Vaccine

• Tetanus is a bacterial infection that causes muscle spasms also known as “lockjaw.” The bacteria reside in the soil and may enter the body through an open wound. Diphtheria is also a bacterial infection that usually spreads via respiratory droplets and causes an illness that usually affects the throat resulting in difficulty breathing but may also affect the skin. Pertussis, also known as “whooping cough” is also transmitted by respiratory droplets and results in violent coughing that can be so severe as to result in fractured ribs. Tetanus and diphtheria are rarely reported in the United States though pertussis remains a more common infection. Tetanus, diphtheria and pertussis vaccination begins in childhood and repeat periodic vaccinations through adulthood are necessary.
• Tetanus containing vaccines are available in two commonly administered adult forms:

1. 1. Tetanus, diphtheria toxoids vaccine (Td) which protects against tetanus and diphtheria.
   2. Tetanus, diphtheria, and acellular pertussis vaccine (Tdap) which protects against all three bacteria.

• The CDC recommends that once an adult has received a Tdap, either a Td or Tdap should be given every 10 years. However, a Tdap may be the better choice for a booster to gain protection from pertussis which may be severe in an immunocompromised individual. Furthermore, it may prevent an adult from passing pertussis on to an infant younger than twelve months of age at very high risk for pertussis complications.
• A booster Td or Tdap may be indicated if five years have passed from the prior vaccine for wounds that are not clean or minor. Again, either vaccine is acceptable though a Tdap may be the better option.

Administration Timing of Inactivated Vaccines

The optimal timing for an inactivated vaccine depends in part on the specific treatment being administered. The National Comprehensive Cancer Network (NCCN), ASCO and 7th European Conference on Infections in Leukemia (ECIL-7) have come up with guidance summarized below:

• Vaccinations are most effective prior to treatment initiation and ideally should be given at a minimum of 2-4 weeks before starting therapy.
• Vaccinations can be given during therapy with a BTK inhibitor or venetoclax alone or in combination though response may be reduced.
• Adjustment in vaccine timing is necessary when anti-CD20 therapy such as rituximab or obinutuzumab is administered.
• Seasonal vaccines such as influenza and COVID-19 should be given 4 weeks or longer following the most recent dose and be repeated at least 6 months or longer after completion of therapy.
• Nonseasonal inactivated vaccines (such as pneumococcal, Hib, HepB, Tdap, HPV, etc) should ideally be given 2-4 weeks before starting or 6-12 months following treatment with an anti-CD20 therapy such as rituximab or obinutuzumab. However, there is one exception, the Shingrix vaccine, which can be given 1 month or longer after the most recent anti-CD20 dose.
• IVIG does not interfere with inactivated vaccines and does not affect timing of vaccinations.

Vaccinations For Individuals Undergoing CAR-T therapy

CAR-T therapy which is gaining broader use for CLL / SLL therapy needs to be mentioned. The therapy targets both healthy and malignant white blood cells resulting in profound immunosuppression and essentially a transient loss of the antibody producing B-cells. It is recommended that all necessary vaccines be given a minimum of 2-4 weeks before the initial lymphodepleting therapy is administered. Because the therapy causes loss of immune memory from earlier vaccinations including those from childhood, full revaccination with a large swath of vaccines is necessary while the immune system reconstitutes and recovers. The American Society of Clinical Oncology (ASCO), the American Society for Transplantation and Cellular Therapy (ASTCT) and a review by Reynolds et al. have released general recommendations for vaccinations following CAR-T cell therapy, and the National Comprehensive Cancer Network  (NCCN) in early 2026 released extrapolated recommendations for vaccinations based on hematopoietic stem cell transplant to CAR-T cell therapy recipients.  I have tried to simplify and consolidate the various recommendations into the below chart. However, recommendations may vary based on physician preference, guideline evolution, individual patient needs and, therefore, it is important to seek guidance from your treating physician.