This brief news release describes the findings from a study of patients with plasma cell disorders, including multiple myeloma, who were given two high-dose injections of Fluzone influenza vaccine in order to lower their risk of contracting the flu during the 2014-2015 flu season. The results were presented at the annual meeting of the American Society of Hematology. While newsy, we think the release should have included more details such as the size of the volunteer group, how the results compared to other vaccination strategies, and the cost and any harms associated with the vaccine. In addition, the headline and presentation of the results may be overly optimistic.
Because of their weakened state, patients with cancers of the immune system are very susceptible to contracting influenza infections. Such patients are not only at a much higher risk of getting the flu but of dying from it. A booster vaccine that lowers risk significantly (without introducing bad side effects to people already feeling weak and sick) would be a welcome addition to the vaccine arsenal.
The news release doesn’t mention any costs associated with the high-dose vaccine.
The New York Times reported last year that “The cost of the high-dose vaccine is $28.65 a dose, and Medicare covers one shot a year without a co-payment.”
The release states that the flu infection rate fell to 6% in the patients who received a booster vaccine 30 days after the first shot, compared to the “expected” rate of 20% infection. We’d much rather see actual numbers here than percentages. How many people were vaccinated with the follow-up booster shot? Was there a comparison group that received only one high-dose shot during the same flu season?
The release also claims that the booster strategy protected against all flu strains in 66% of patients. Again, 66% of how many?
The study was small with just 51 patients. To say the vaccine lowered the infection rate to 6% is misleading because there was no comparison group. It would have been helpful to point out that a 6% infection rate is lower than historical controls, but that the effectiveness needs to be studied in a controlled clinical trial to really see the benefit.
The release doesn’t mention any of the harms associated with the vaccine.
While influenza vaccine is generally safe, there are some potential adverse reactions that are more common with the high dose formulation. According to a news release from Sanofi-Pasteur, the manufacturer of Fluzone, announcing updated prescribing information for Fluzone high-dose in patients 65 and older: “The most common local and systemic adverse reactions to Fluzone High-Dose vaccine include pain, erythema, and swelling at the injection site; myalgia, malaise, headache, and fever. Other adverse reactions may occur. Fluzone High-Dose vaccine should not be administered to anyone with a known hypersensitivity (eg, anaphylaxis) to any vaccine component, including egg protein, or to a previous dose of any influenza vaccine.”
As mentioned above under “Benefits,” the release doesn’t describe the study protocol. We must assume it wasn’t a randomized, controlled trial — but what kind of study was it? How many were enrolled? Where was the patient population drawn from?
According to the study abstract posted online, 51 patients were enrolled, 41 of whom were undergoing treatment and 10 who had no symptoms but their pathology showed they had abnormal proteins in their blood. The median age was 75 years old. Upon follow-up, just 4% — or 2 out of the 51 patients — developed influenza.
A study of this size with no comparison group cannot make determinations about effectiveness and can only give a glimpse at safety.
The release accurately points out the higher risk of contracting flu among patients with multiple myeloma and other cancers of the immune system without unnecessary fear-mongering.
The release discloses that the study was funded by the Yale Cancer Center’s Arthur R. Sekerak Cancer Research Fund.
Although this study examines a novel approach, it is still necessary to compare it to existing protocols. At minimum, we would like to know how the booster strategy compared with the single vaccination. We’re told the outcome is better with the novel strategy but we aren’t provided any of the data.
The release notes that the Fluzone high-dose vaccine used in the study was approved by the FDA in 2009.
A booster dose would currently be considered an “off label” use and may not be covered by insurance.
The release notes that using a follow-on booster of the high-dose vaccine is a novel flu prevention strategy in patients with cancers that affect the immune system. This approach of adding a booster is used in immune-suppressed patients with other vaccines as well.
The release doesn’t use overly unjustifiable language.