key: cord-1017914-c5viy9f2
authors: Thomas, Stephen J.; Perez, John L.; Lockhart, Stephen P.; Hariharan, Subramanian; Kitchin, Nicholas; Bailey, Ruth; Liau, Katherine; Lagkadinou, Eleni; Türeci, Özlem; Şahin, Ugur; Xu, Xia; Koury, Kenneth; Dychter, Samuel S.; Lu, Claire; Gentile, Teresa C.; Gruber, William C.
title: Efficacy and safety of the BNT162b2 mRNA COVID-19 vaccine in participants with a history of cancer: subgroup analysis of a global phase 3 randomized clinical trial
date: 2021-12-24
journal: Vaccine
DOI: 10.1016/j.vaccine.2021.12.046
sha: 0ec0c46d3c55b13aac2e1fea580a86de558965ac
doc_id: 1017914
cord_uid: c5viy9f2

INTRODUCTION: Individuals with an underlying malignancy have high risk of poor COVID-19 outcomes. In clinical trials, COVID-19 vaccines were safe and efficacious against infection, hospitalization, and death, but most trials excluded participants with cancer. We report results from participants with a history of past or active neoplasm (malignant or benign/unknown) and up to 6 months’ follow-up post-dose 2 from the placebo-controlled, observer-blinded trial of the 2-dose BNT162b2 mRNA COVID-19 vaccine. PATIENTS AND METHODS: Between July 2020–January 2021, 46,429 participants aged ≥12 years were randomized at 152 sites in 6 countries. Healthy participants with pre-existing stable neoplasm could participate; those receiving immunosuppressive therapy were excluded. Data are reported for participants, aged ≥16 years for safety and ≥12 years for efficacy, who had any history of neoplasm at baseline (data cut-off: March 13, 2021). Adverse-event (AE) data are controlled for follow-up time before unblinding and reported as incidence rates (IRs) per 100 person-years follow-up. RESULTS: At baseline, 3813 participants had a history of neoplasm; most common malignancies were breast (n = 460), prostate (n = 362), and melanoma (n = 223). Four BNT162b2 and 71 placebo recipients developed COVID-19 from 7 days post-dose 2; vaccine efficacy was 94.4% (95% CI: 85.2, 98.5) after up to 6 months’ follow-up post-dose 2. This compares favorably with vaccine efficacy of 91.1% in the overall trial population after the same follow-up. AEs were reported at IRs of 95.4 (BNT162b2) and 48.3 (placebo) per 100 person-years. Most common AEs were reactogenicity events (injection-site pain, fatigue, pyrexia). Three BNT162b2 and 1 placebo recipients withdrew because of vaccine-related AEs. No vaccine-related deaths were reported. CONCLUSION: In participants with past or active neoplasms, BNT162b2 vaccine has a similar efficacy and safety profile as in the overall trial population. These results can inform BNT162b2 use during the COVID-19 pandemic and future trials in participants with cancer. Clinical trial number: NCT04368728

Compared with the general population, people with cancer are at increased risk for adverse outcomes due to coronavirus disease 2019 (COVID- 19) , including hospitalization, intensive care unit admission, intubation or mechanical ventilation, and death (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) . People with cancer often also have a number of additional risk factors, including lung inflammation, immunosenescence, and comorbidities that may predispose them to adverse COVID-19 outcomes (7) . Active cancer and recent or current cancer-specific therapy, including treatment with immune checkpoint inhibitors, appear to confer higher risk of severe COVID-19 and mortality (1) (2) (3) (4) (5) (6) (7) (8) (9) 11) . Advanced age, male sex, and underlying hematologic malignancy also confer a particularly high risk for adverse outcomes (1-6, 9, 11) .

Recommendations for cancer management during the COVID-19 pandemic have emphasized balancing the risk of exposure to the SARS-CoV-2 virus, while avoiding unnecessary delays in cancer treatment (12) (13) (14) . Patients with a history of malignant tumors may have compromised immunity due to immunosenescence, prior treatments, and comorbidities, which may hinder the efficacy of COVID-19 vaccines. However, many vaccine trials excluded participants with active cancer or who were receiving immunosuppressive treatments. The randomized, placebo-controlled, observer-blinded phase 1/2/3 trial of the BNT162b2 mRNA COVID-19 vaccine (COMIRNATY®, tozinameran; Fig. 1) included a significant number of participants with a history of neoplasm (malignancy or benign/unknown tumor) at baseline, either past or active (those receiving immunosuppressive treatment were excluded). In response to the need for direct evidence of vaccine efficacy and safety in people with cancer, we report a post hoc subgroup analysis of clinical efficacy and safety in participants with a history of neoplasm from this study. In the overall trial population, BNT162b2 was 95% effective in preventing COVID-19 from 7 days post-dose 2 in participants ≥16 years of age after a median follow-up of 2 months (18) . Subsequent analyses in adolescents (aged 12-15 years) demonstrated non-inferior immunogenicity relative to young adults (aged 16-25 years), and 100% efficacy was observed (19) . Updated vaccine efficacy after up to 6 months of follow-up in the overall trial population remained high after dose 2 (91%) (20) . On the basis of these results, in December 2020, the BNT162b2 COVID-19 vaccine was granted Emergency Use Authorization by the US FDA and conditional marketing authorization in the European Union for immunization of individuals ≥12 years of age (21-23). The BNT162b2 COVID-19 vaccine was subsequently granted issuance of a license from the FDA following a Biologics License Application on August 23, 2021, for use in individuals ≥16 years of age (24). The current post hoc subgroup analysis included trial participants who at baseline had a prior diagnosis of any malignancy or other neoplasm (ie, including benign tumors and those with unknown etiology), but who were not receiving immunosuppressive therapy.

The randomized, placebo-controlled, observer-blinded global phase 3 clinical trial of the vaccine was conducted as part of a phase 1/2/3 trial (NCT04368728) to evaluate BNT162b2 safety, immunogenicity, and efficacy. The study design and population have been described in detail elsewhere (18, 19) ; aspects relevant to the present subgroup analysis are summarized below.

Healthy male and female participants aged ≥12 years were randomized 1:1 to receive 2 doses of the BNT162b2 vaccine (30 µg) or saline placebo, administered 21 days apart, delivered in the deltoid muscle. The primary objectives were to evaluate BNT162b2 efficacy against laboratory-confirmed COVID-19 occurring from 7 days after the second vaccine dose and to define the safety profile. After external data monitoring committee review and Emergency Use Authorization by the FDA on December 10, 2020, participants were allowed to unblind and those in the placebo arm could crossover and receive the vaccine. Blinded, placebo-controlled data prior to unblinding for crossover up to March 13, 2021 , are reported herein. Participants had up to 6 months of follow-up post-dose 2 prior to unblinding.

A total of 46,429 participants aged ≥12 years were randomized at 152 sites in 6 countries between July 2020 and January 2021.

A full list of inclusion and exclusion criteria is available in the study protocol as reported elsewhere (18) . Healthy participants with pre-existing stable neoplasm, ie, not requiring a significant change in their cancer therapy or hospitalization for worsening disease during the 6 weeks before enrollment, were eligible to participate in the study. Exclusion criteria included clinical or virologic COVID-19 diagnosis or SARS-CoV-2 infection prior to vaccination, previous coronavirus vaccination, or diagnosis of an immunocompromising or immunodeficiency disorder. Individuals receiving immunosuppressive therapy including cytotoxic agents or systemic corticosteroids, e.g., for cancer or an autoimmune disease were excluded. Participants who received short-term (<14 days) corticosteroids for treatment of an acute illness could enroll in the study ≥28 days after corticosteroid therapy discontinuation. Prohibited medications (resulting in exclusion from per protocol analyses) within 60 days before enrollment through study conclusion included chronic systemic treatment with known immunosuppressant medications, radiotherapy, and treatment with blood/plasma products or immunoglobulins.

Medical history was collected at baseline and categorized according to Medical Dictionary for Regulatory Activities (MedDRA) system organ class and preferred term; the numbers and proportions of participants with comorbidities that increase the risk for severe COVID-19 illness were determined by vaccine group, according to the pre-specified trial statistical analysis plan. We report post hoc analyses of efficacy and safety data from subgroups of participants with any cancer-related medical history at baseline. Because immunosuppressive therapy was an exclusion criterion for the study, patients with cancer who were actively receiving cytotoxic immunosuppressive agents or immune checkpoint inhibitors were not included in the study. For the purposes of the present analysis, the subgroup of participants with a history of cancer was defined as participants who had a history of past or active malignancy or other neoplasm (including benign neoplasms and those of unknown etiology). Medical history data were reviewed and participants were further classified according to history of malignant tumor, benign tumor, or other non-specific neoplasm (including those with unknown etiologies). Additional supportive post hoc analyses were performed for the subset of participants with malignancies only (ie, excluding those with benign neoplasms or those with unknown etiologies); separate analyses were also performed for subsets of participants with solid and hematologic malignancies.

Participants were monitored for potential COVID-19 throughout the trial and tested for SARS-CoV-2 if they developed symptoms potentially indicative of COVID-19. Vaccine efficacy was evaluated in all randomized participants aged ≥12 years who received both doses within acceptable time frames and had no major protocol deviations (evaluable efficacy population). BNT162b2 efficacy against confirmed COVID-19 with an onset of 7 or more days after the second vaccine dose was summarized in participants without serologic or virologic evidence of SARS-CoV-2 infection up to 7 days after the second dose and in all vaccinated participants regardless of evidence of prior infection (18, 19) .

Participants reported all adverse events (AEs) and serious AEs from receipt of the first vaccine dose through 1 month and 6 months, respectively, after the second vaccine dose. For the present analysis, the safety population included all participants ≥16 years of age who received at least 1 dose of the study intervention. AEs were summarized for each vaccine group by relationship to study vaccine as judged by the investigator, severity, and MedDRA (v23.1) system organ class and preferred term. AE data are controlled for follow-up time before unblinding and reported as incidence rate (IR) per 100 person-years of blinded follow-up, calculated as the number of participants reporting an event over the total exposure time, from dose 1 to end of blinded followup, across all participants in the group. Corresponding exact 2-sided 95% confidence intervals (CIs) were determined on the basis of the link between the Poisson and Chi-square distributions.

CONSORT diagrams of study flow and baseline characteristics of the overall trial population have been previously published (18, 19) . Among 44,047 participants aged ≥16 years in the overall trial population, 3813 participants had a history of any neoplasm (malignant or benign/unknown) at baseline (past or active; however, those on active immunosuppressive treatment were excluded from the trial). Overall, the majority of these participants were female (63.3%), white (88.7%), and from the US (91.2%) ( Table 1) . Participants in this subgroup tended to be older than in the overall trial population (median age of 64.0 years and 51.0 years, respectively; Table 1 ).

Among the 3813 participants included in the current analysis, 2335 participants had a past or active malignant tumor, including 149 with an active malignancy at baseline, while 1478 had a benign or unknown tumor ( Table 2) . Most malignancies were solid tumors (n = 2259), most commonly breast cancer (n = 460), prostate cancer (n = 362), and melanoma (n = 223). Relatively few participants (n = 97) had a history of hematologic malignancy, which included lymphomas and leukemias.

Among 3538 evaluable participants aged ≥12 years with a history of any past or active neoplasm (malignant or benign) and without evidence of prior SARS-CoV-2 infection, there were 4 COVID-19 cases with onset from 7 days through 6 months post-dose 2 in BNT162b2 vaccine recipients versus 71 cases in placebo recipients, representing vaccine efficacy of 94.4% (95% CI: 85.1, 98.5) ( Table 3) 

AEs were reported over a total exposure time (ie, dose 1 to end of blinded follow-up) of 700 person-years for both the BNT162b2 vaccine and placebo recipient groups with a history of any neoplasm (malignant or benign/unknown). AEs and vaccine-related AEs were reported more frequently among BNT162b2 (IR: 95.4 and 69.4 per 100 person-years exposure, respectively) than placebo recipients (IR: 48.3 and 16.7, respectively) ( Table 4 ). AEs were generally reported at slightly higher IRs in this subgroup than in the overall clinical trial population. Few participants with a history of neoplasm reported severe AEs (IR: 5.6, BNT162b2; 3.6, placebo; per 100 person-years) or serious AEs (IR: 6.7, BNT162b2; 3.6, placebo). Two BNT162b2 vaccine recipients reported serious AEs that were considered vaccine-related: 1 participant experienced ventricular arrhythmia on the day of dose 2 and 1 experienced lymphadenopathy on day 13 post-dose 1 (this participant also experienced non-serious vaccine-related AEs of chills, injection-site erythema, injection-site pain, and injectionsite warmth, and withdrew from the study because of AEs). Both serious vaccine-related AEs resolved. Six BNT162b2 vaccine recipients and 4 placebo recipients withdrew from the study because of AEs; among them, 3 and 1 participants, respectively, withdrew because of AEs that were considered vaccine-related (all reactogenicity events; BNT162b2: 1 participant with lymphadenopathy as described above, 1 participant with injection-site swelling on the day of dose 1, and 1 participant with abdominal discomfort, diarrhea, eye pain, fatigue, headache, and muscle weakness on the day after dose 1; placebo: 1 participant with cheilitis, dry mouth, dysgeusia, eczema, parosmia, pruritus, and maculo-papular rash on day 16 after placebo dose 1). Three participants died during the study (1 in the BNT162b2 group and 2 in the placebo group); none of the deaths were considered vaccine related.

Consistent with the previously reported safety profile for the full clinical trial population (18, 19) , the most common AEs (any causality) were reactogenicity events, including injection-site pain, fatigue, and pyrexia ( Table 4 ). These events were reported at similar IRs in the subgroup of participants with a history of neoplasm as in the overall trial population during the same follow-up period.

The frequency and pattern of AEs were similar among the subset of participants who had past or active malignant neoplasms only as for the overall subgroup of participants with a history of any neoplasm (malignant or benign/unknown) ( Table 5 ).

Approximately 8% of participants (>3800) from the phase 3 trial of the BNT162b2 mRNA COVID- In the primary analysis of BNT162b2 vaccine efficacy, the vaccine demonstrated high efficacy against COVID-19 infection, with 95% vaccine efficacy observed at least 7 days after the second vaccination in the overall clinical trial population (18) , and similarly high efficacy (91%) observed in the overall population of participants aged ≥12 years at a subsequent analysis after up to 6 months of follow-up post-dose 2 (20) . The high efficacy observed in the current analysis of participants with a history of any past or active neoplasm (malignant or benign/unknown; 94%) and those with malignant neoplasms only (93%) compares favorably with these results. The BNT162b2 vaccine had a favorable safety profile in the subgroup of participants with a history of any neoplasm, with an AE profile generally consistent with that observed in the overall study population (18) . The most common AEs were reactogenicity events, including injection-site pain, fatigue, and pyrexia, and very few AEs were severe in intensity. The favorable safety and tolerability profile of BNT162b2 in our analysis is in agreement with results recently reported from real-world COVID-19 vaccine studies that included individuals with active cancer and those receiving anticancer treatment (30) (31) (32) (33) .

Patients with cancer may receive systemic immunosuppressive therapies as part of their anticancer treatment, which has broadly resulted in exclusion of these patients from the randomized, phase 3 COVID-19 vaccine trials (18, (34) (35) (36) (37) . Indeed, the present subgroup analysis is based on participants with a history of cancer who were not receiving active immunosuppressant therapy, because this was an exclusion criterion for the BNT162b2 vaccine clinical trial (18) . The phase 3 study of the Ad26.COV2.S vaccine (Johnson & Johnson) included a small number of participants with cancer at baseline (0.5%) but excluded participants receiving antineoplastic and immunomodulating agents or radiotherapy within 6 months before enrollment (34) . Similarly, the phase 3 trial of the mRNA-1273 COVID-19 vaccine (Moderna) excluded participants receiving systemic immunosuppressants or immune-modifying drugs (36) . Although subgroup analyses of participants with certain pre-existing conditions associated with severe COVID-19 (e.g., chronic lung disease and significant cardiac disease) have been reported from that study, results from participants with cancer were not reported (36) .

Since the efficacy of COVID-19 vaccines in patients with cancer receiving active antitumor systemic treatment has not been evaluated in the randomized, controlled trial setting, real-world effectiveness data will be essential to better understand the clinical profile of COVID-19 vaccines in these patients. Indeed, initial real-world data are beginning to be reported from cohort studies of patients with cancer who have received COVID-19 vaccines, including the BNT162b2 mRNA COVID-19 vaccine (30) (31) (32) (33) (38) (39) (40) . The results have provided encouraging safety data and suggested a similar AE profile for the BNT162b2 vaccine among patients with cancer (including those treated with checkpoint inhibitors) (30) (31) (32) (33) (41) (42) (43) as that observed in the overall randomized clinical trial population (18) (19) (20) .

In recent real-world studies, lower serological responses to COVID-19 vaccination regimens have generally been reported in cohorts of patients with hematologic malignancies compared with patients with solid tumors and healthy controls, with the lowest responses among patients on active treatment (25-29, 44, 45) . Particularly low antibody responses to the first BNT162b2 vaccine dose have been reported in patients with cancer, highlighting the potential importance of additional doses (27, 32, 39, 40, 43, 46) . Even with two vaccine doses, many patients with hematologic malignancies remain at risk for not producing adequate antibody responses (25) (26) (27) (28) (29) (30) . In a recent cohort study of patients with solid and hematologic cancer (n = 88), a third COVID-19 vaccine dose potentiated immune responses in most patients, although a few patients (particularly those who received anti-CD20 therapy) did not have a serological response even after a third dose (26) . The ability to draw conclusions about the safety and efficacy of the BNT162b2 vaccine in patients with hematologic malignancies in our subgroup analysis is limited by the very low number of participants with a history of these types of malignancies (<3%; n = 97). In this small subset of participants with a history of hematologic malignancies, one case of COVID-19 was reported in a BNT162b2 vaccine recipient with a history of lymphoma >20 years prior to study vaccination, and one case was reported in a placebo recipient.

Data from cohort studies of patients with solid tumors receiving anticancer treatment indicate that most patients mount an acceptable antibody response after 2 doses of BNT162b2, but antibody titers are generally lower than in people without cancer (27, 38, 47, 48) . For example, among 102 patients with solid tumors receiving anticancer treatment at a single Israeli center, 92 (90%) patients and all (78/78) healthy controls were seropositive for SARS-CoV-2 anti-spike IgG 13-54 days after receiving a second BNT162b2 dose, with durable seropositivity (87%) observed among the patients with cancer after 4 months of follow-up (38, 49) . However, despite this high seroconversion rate, significantly lower IgG titers were observed among the patients with cancer versus controls in that study (38, 49) .

Emerging real-world effectiveness results following mass BNT162b2 vaccination campaigns, which included people with cancer and other underlying health conditions, have been generally consistent with the high efficacy observed in the phase 3 clinical trial (18, 19) , but specific data on BNT162b2 antibody responses and efficacy in subsets of people with cancer have not been reported (50, 51) . One recent descriptive report of >6000 individuals with cancer vaccinated with BNT162b2 from a single US institution showed low rates of breakthrough infection (1 case) with no unexpected safety signals; however, this study did not include a placebo/unvaccinated control group or a comparator group of vaccine recipients without cancer (33) . Similarly, low rates of COVID-19 were reported in patients with cancer who received 2-dose COVID-19 vaccine regimens at a single center in France (52) . It remains unclear whether the lower antibody responses observed in some cohort studies translate into a difference in COVID-19 vaccine efficacy in people with cancer; therefore, efficacy/effectiveness data in these populations are needed to understand the level of protection.

As described above, limitations of this analysis include the exclusion of participants receiving concurrent immunosuppressive therapy (e.g., chemotherapy) from the trial and the low number of participants with active cancer and hematologic malignancies. This selected clinical trial population may not reflect the heterogeneous group of patients with cancer. In addition, these observations came largely from white participants, and results may not be generalizable to people of other racial identification. Participants in the subgroup tended to be older than those in the overall study population. Since this was a post-hoc subgroup analysis, the study was not powered for formal 

The BNT162b2 mRNA COVID-19 vaccine demonstrated robust efficacy and acceptable safety in clinical trial participants with a history of past or active neoplasms, who were not receiving immunosuppressive treatment, and who had up to 6 months of follow-up post-dose 2. The efficacy and safety in these participants were similar to the overall clinical trial population. These results support the current recommendations to consider immunizing people living with cancer against COVID-19 using the BNT162b2 mRNA COVID-19 vaccine and provide the foundation to plan future trials in these populations. 

The authors thank all of the participants who volunteered for this study, and the C4591001 Clinical Trial Investigators and study-site personnel. Medical writing assistance was provided by Erin Bekes, PhD, of CMC AFFINITY, McCann Health Medical Communications, and was funded by Pfizer.

This work was supported by Pfizer and BioNTech. No grant number is applicable.

Upon request, and subject to review, Pfizer will provide the data that support the findings of this study. Subject to certain criteria, conditions and exceptions, Pfizer may also provide access to the related individual de-identified participant data. See https://www.pfizer.com/science/clinicaltrials/trial-data-and-results for more information.

Pfizer was responsible for the design and conduct of the trial, data collection, and the data analysis.

BioNTech was the sponsor of the trial and manufactured the BNT162b2 clinical trial material. All authors were involved in data interpretation as well as the writing, reviewing, and approving of the manuscript. All trial data were available to all the authors, who vouch for its accuracy and

completeness. An independent data and safety monitoring board reviewed efficacy and unblinded safety data. Table 1 Demographic and baseline disease characteristics of the subgroup of participants with any history of past or active neoplasm (malignancy or benign/unknown tumor) at baseline and the overall trial population, by vaccine group (safety population). Vaccine efficacy against COVID-19 at least 7 days after the second vaccine dose among participants with any history of past or active neoplasm (malignancy or benign/unknown tumor) at baseline and the overall trial population (evaluable efficacy population). Injection-site swelling 

☐ The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

☒ The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:

Stephen Thomas reports financial support was provided by Pfizer Inc. Stephen J Thomas reports a relationship with Clover that includes: consulting or advisory. Stephen J. Thomas reports a relationship with Iscovaxx that includes: consulting or advisory. Stephen J. Thomas reports a relationship with GeneOne that includes: funding grants. Pfizer -one time consulting activity for vrbpac meeting in DEC 20

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COVID-19 = coronavirus disease

NAAT = nucleic acid amplification test

a Positive N-binding antibody result at Visit 1, positive NAAT result at Visit 1, or medical history of COVID-19