. 49 Version number: 6.0, 27 December 2021 9 of 49 LIST OF ABBREVIATIONS AND RELEVANT DEFINITIONS AE Adverse Event AESI Adverse Event of Special Interest ALAT Alanine aminotransferase ASAT Aspartate aminotransferase CBG College ter Beoordeling van Geneesmiddelen CBS Centraal Bureau voor de Statistiek CI Confidence Interval COVID -19 Coronavirus Disease 2019 CRP C-reactive protein CTCAE Common Terminology Criteria for Adverse Events DSMB Data Safety Monitoring Board ECOG PS Eastern Cooperative Oncology Group Performance Status EMA European Medicines Agency EU European Union GBA Gemeentelijke Basis Administratie GCP Good Clinical Practice GMC Geometric Mean C oncentration IC Informed Consent ICI Immune Checkpoint Inhibitor IKNL Integraal Kankercentrum Nederland IFN-ɣ Interferon -gamma irAE immune r elated Adverse Event IST Investigator Sponsored Trial METC Medical research ethics committee (MREC); in Dutch: medisch -ethische toetsing scommissie (METC) MIA Multiplex Immunoassay NIBSC National Institute for Biological Standards and Control PBMC Peripheral Blood Mononuclear Cells PD1 Programmed Death 1 (immune checkpoint) PD-L1 Programmed Death -ligand 1 (immune checkpoint) PIF Participant Information Form (S)AE (Serious ) Adverse Event SARS - CoV-2 Severe Acute Respiratory Syndrome Coronavirus 2 SPC Summary of Product Characteristics ; in Du tch: officiële productinform atie Version number: 6.0, 27 December 2021 10 of 49 IB1-tekst Sponsor The sponsor is the party that commissions the organisation or performance of the research, for example a pharmaceutical company, academic hospital, scientific organisation or investigator. A party that provides funding for a study but does not commission it is not regarded as the sponsor, but referred to as a subsidi sing party. SUSAR Suspected Unexpected Serious Adverse Reaction WHO World Health Organization WMO Medical Researc h Involving Human Subjects Act; in Dutch: Wet Medisch - wetenschappelijk Onderzoek met Mensen Version number: 6.0, 27 December 2021 11 of 49 SUMMARY Rationale: Patients with cancer have an increased risk of adverse outcome of COVID -19, which is determined by their underlying disease and/or cancer treatment. Therefore , vaccination of cancer patients against COVID -19 is recommended . However, phase III studies do not provide robust information on efficacy and safety in this vulnerable population. In patients with cancer, the disease itself, but also immunotherapy and chemotherapy, may have a significant impact on the ability to develop an effective immune response to COVID - 19 vaccina tion, and could even increase the risk of adverse events. Objective : To assess immune response and adverse events after administration of one approved vaccine against COVID -19 in patients with cancer treated with immunotherapy and/or chemotherapy . Study design: This is a prospective multicenter , multicohort study. Study population: Four cohorts will receive vaccination against COVID -19: A. Individuals without cancer (N=246, i.e., partners of patients in cohort B, C, and D) B. Patients with cancer treated with immunotherapy (N=135) C. Patients with cancer treated with chemotherapy (N=246) D. Patients with cancer treated with chemo -immunotherapy (N=246) Main inclusion criteria: - age of 18 years or older - life expectancy > 12 months - ability to provide informed consent - last immunotherapy cycle within 3 months of vaccination (cohort B and D) - last chemotherapy cycle within 4 weeks of vaccination (cohort C and D) Main exclusion criteria: - confirmed SARS -CoV-2 infection (cur rent or previous) - women who are pregnant or breastfeeding - active hematologic malignancy - immune deficiency not related to cancer or cancer treatment - systemic treatment with immune suppressive medication, including chronic steroid use of >10 m g prednisone or equivalent Version number: 6.0, 27 December 2021 12 of 49 Intervention : Participants will be vaccinated against COVID -19 with an approved vaccine . Blood will be drawn at different time points by venipuncture and mucosal lining fluid will be collected at 2 time points . Main study parameters /endpoints : The primary endpoint is the antibody based immune response on day 28 after the second vaccination . Participants will be classified as responders or non -responders. The definition of response is seroconversion defined as presence of SA RS-CoV-2 spike S1 -specific IgG antibodies in individuals without measurable anti-S antibodies at baseline. Participants who are seropositive at baseline will not be included in the analysis of the primary endpoint. The percentage of responders of each patient cohort will be compared with the percentage responders in the control group. Safety is a secondary endpoint which will be reported in terms of percentage of solicited local and systemic adverse events (AEs) graded according to severity . Other secondary endpoints include longevity at 6 months and levels of SARS -CoV-2 specific T cell responses. Nature and extent of the burden and risks associated with participation, benefit and group relatedness: Participants will have to visit the hospita l at 6 time points , and participants who receive a third vaccination will have 2 additional hospital visits . The vaccin e will be administered two times according to the standard of care , with the option of a third vaccination for participants without an ad equate response after 2 vaccinations . Blood will be drawn (~373 ml in total for participants receiving 2 vaccinations, and ~539 ml in participants receiving 3 vaccinations ) prior to the vaccinations and at day 28 and 6 months , 11 months and 18 months after the second vaccination. Nasal m ucosal lining fluid samples will be collected at baseline and day 28 after the second vaccination in a subgroup of patients. Blood sampling will give minor discomfort , mucosal lining fluid collection is a non -invasive procedure . Vaccination can cause AEs including fatigue, chills, headache, myalgia, and pain at the injection site. For seven days after each vaccination, p articipants will be asked to record local and systemic reactions using a questionnaire . At baseline a nd at 3, 6, 9 ,12, 15 and 18 months after the second vaccination , patients will be asked to complete questionnaires about potential subsequent testing for SARS -CoV-2, diagnosis of COVID -19, and severity of COVID -19. This study will collect information on immune response and adverse events after vaccination against COVID -19 in a vulnerable patient cohort . It will also explore immune response and safety of a third vaccination in participants without an adequate antibody response after the second vaccination. Understanding the ability or disability to mount a protective immune response after vaccination will help to counsel patients during the pandemic and support Version number: 6.0, 27 December 2021 13 of 49 decisions on whom to vaccinate and to identify patients who require other measures to protect the m from COVID -19. Participants will be informed about their antibody titer in a letter that includes an explanation about what this means to them. This will be done after antibody measurements have been completed for day 28 after second vaccination, and again after completion of measurements for 6 months and 28 days after third vaccination , and 11 months and 18 months after the second vaccination . 1. INTRODUCTION AND RATIONALE 1.1 Impact of COVID -19 pandemic on onco logical care The SARS -CoV-2 pandemic is having a huge impact on societies all around the globe. As of December 8, 2020 , over 65 million people have been diagnosed with Coronavirus induced disease (COVID -19), resulting in over 1 ,5 million deaths with numbers still incre asing [1,2]. Over the past 6 months, regular health care , including cancer care [3,4], has been scaled down because hospitals were flooded with patient s with COVID -19. In addition, hospital visits for anticancer therapies may put patients at even more risk of getting infected with SARS - CoV-2 [5,6]. As the COVID -19 pandemic overwhelmed healthcare systems worldwide, non - evidence -based decisions had to be made about the treatment of patients with cancer. Consequently, oncological treatment was frequently adjus ted during the COVID -19 pandemic, even in regions with relatively low COVID -19 incidence [3]. These treatment adjustments were made according to COVID -19 guidelines of (inter)national oncological societies, which were primarily based on expert opinions [7-10]. The limited capacity to deliver cancer care, the lockdown isolating patients at home, and their fear of entering hospitals, has led to suboptimal cancer care. In addition, there was a 30% underdiagnosis and delayed diagnosis of cancer in the Netherlan ds [11,12]. This most likely will result in higher cancer -specific mortality rates in the years to come. 1.2 Outcome of COVID -19 in patients with cancer Patients with cancer have a higher risk for a dismal outcome of COVID -19 [13-15]. Therefore, international registries have been initiated to identify the clinical characteristics of cancer patients with severe COVID -19 [5,6, 16-25]. The worse outcome of COVID -19 in patients with cancer is determined by their underlying disease and/or cancer treatment . In particular, lung cancer and hematological malignancies are independent risk factors for a fatal outcome of COVID -19 [4]. In addition, chemotherapy and chemo -immunotherapy have been identified as risk factor s for mortality of COVID -19 in patie nts with cancer [26,27] . 1.3 COVID -19 vaccination Version number: 6.0, 27 December 2021 14 of 49 Several v accines are currently in development and the RNA vaccines by BioNTech/Pfizer and Moderna [28-31], were granted conditional marketing authorization by EMA . Vaccination of the Dutch population has started in January 2021. For the VOICE study the mRNA -1273 SARS -CoV-2 vaccine from Moderna will be used. In the randomized phase III study with mRNA -1273 , 30,420 volunteers received two intramus cular injections of the vaccine (100 ug) or placebo 28 days apart [32]. None of the participants was treated with chemotherapy and/or immunotherapy for cancer at the time of vaccination. In the placebo group 185 participants developed symptomatic COVID -19 versus 11 participants who received the vaccine, resulting in 94.1% vaccine efficacy (95% CI, 89.3 to 96.8%; P<0.001) . Severe COVID -19 only occurred in the placebo group : in 30 participants including one fatality. Solicited AEs at the injection site were common in the vaccine group (84.2% after the first injectio n and 88.6% after the second injection) but mainly low grade and of short duration. Solicited systemic AEs in this group were reported by 54.9% of the participants after the first dose and by 79.4% after the second dose, and mainly consisted of headache, f atigue, myalgia and chills. The rate of unsolicited AEs and SAEs up to 28 days after vaccination was similar in both arms. Hypers ensitivity reactions occurred in 1.5% in the vaccine group and 1.1% in the placebo group. 1.4 COVID -19 vaccination in patients with cancer Patients with cancer have an increased risk for an adverse outcome of COVID -19 [13-15]. As a consequence , many patients strictly adhere to self -isolation, resulting in loneliness and loss of quality of life. Therefore, vaccination needs to be prioritized for these vulnerable patients. In addition, effective COVID -19 vaccination is of extreme importance to protect patients with cancer to continue care and cure. An immune response to vaccination would not only protect them from life-threatening C OVID -19 but also allow close contact with their loved ones. Therefore, patients and patient organizations have already claimed prioritization of vaccination against COVID -19 for patients with cancer . For proper protection against COVID -19 by vaccination, specific immune responses need to be induced. SARS -CoV-2 specific immune cells are essential to combat the virus. B cells are important for antibody responses to neutralize the virus, while CD8 positive T cells can specifically recognize and eradicate viru s-infected cells . In addition, CD4 positive T cells are required for providing necessary help to B cells and CD8 positive T cells . Cancer immunotherapy activates T cells against cancer cells by blocking the interaction between Programmed Death 1 (PD1) and its ligand (PD -L1) [33]. How this treatment impacts immune response s to vaccination is unknown. Chemotherapy causes bone marrow suppression and reduces the number of immune cells in the blood circulation, which may hamper the induction of protective immune responses after vaccination as suggested in studies on Version number: 6.0, 27 December 2021 15 of 49 influenza vaccination [34]. However, it is striking how little information is available on safety and efficacy of vaccination in cancer patients. As compared to the healthy population, patients with cancer treated with immunotherapy and/or chemotherapy may be more prone to adverse events of vaccination. Immunotherapy could potentially result in an augmented immune response to vaccination resulting i n fever, chills , and other immune -related adverse events. Chemotherapy is known for significant fatigue, which impacts performance status and increases vulnerability. As a result, immunotherapy and chemotherapy may have a significant impact on the effectiv eness but also on the safety of COVID -19 vaccination. In several countries including Belgium and France, immunocompromised patients are now offered a third vaccination. An advice from the Dutch Health Council about additional vaccination of immunocompromised patients in the Netherlands is expected soon. To protect patients with cancer from COVID -19, clinical trials are urgently needed to evaluate whether they develop an effective, safe , and durable immune response during immunotherapy and/or chemotherapy. 1.5 Current trial The one central question is whether patients with cancer and especially those requiring systemic treatment, can develop protective immunity against COVID -19 upon vaccination. This question needs to be answered urgently and would help the medical oncology community to decide whether optimal cancer care can be delivered safely to vaccinated patients with cancer. In the VOICE trial , this important question will b e addressed in a longitudinal cohort in which patients with solid cancer s requiring systemic therapy will be vaccinated with the available COVID -19 vaccine according to the Dutch vaccination program . Patients with hematologic malignancies are not included in this study because it is known from influenza vaccination studies that those patients are frequently not able to build an effective immune response [35]. This means that protection of patients with a hematologic malignancy may require a different protective strategy such as treatment with SARS -CoV-2 specific antibodies. In the VOICE study, t he ability to mount antibody responses , will be measured in three cohorts of patients treated with chemotherapy, immunotherapy, or chemo -immunotherapy. Their immune response to COVID -19 vaccination will be compared to the immune response of participants without cancer and vaccinated with the same vaccine . Next to measuring antibody responses and their kinetics over time, also an in -depth analysis of T cell immunity, side effects of vaccination, SARS -CoV-2 infection rate, and severity of COVID -19 will be assessed. The VOICE trial will address a high unmet medical need, i.e., vastly gathering information on vaccine safety and effectiven ess in one of the most vulnerable populations and could serve as a model for studies in other fragile populations. Understanding the ability Version number: 6.0, 27 December 2021 16 of 49 or disability to mount a protective immune response to a COVID -19 vaccine will help to counsel patients with cancer during th is pandemic. Moreover, it will support deci sions how to administer the best cancer care safely . 1.6 First results VOICE trial Between February 17th and March 12th, 2021, 791 participants were enrolled in the current trial. For the primary endpoint at 28 days after the second vaccination, 743 participants were evaluable (per -protocol population): 240 individuals without cancer and 131 patients receiving immunotherapy, 229 patients receiving chemotherapy, and 143 patients receiving chemo -immunotherapy. SARS -CoV-2-binding antibody response (>10 binding antibody units (BAU)/mL) was found in 100%, 99.3%, 97.4%, and 100% of the particip ants in cohorts A, B, C, and D, respectively. Given the importance for clinical decisions, we defined, based on neutrali zing capacity, a cut - off level at 300 BAU/mL to discriminate between suboptimal and adequate responders. Twenty eight days after the second vaccination, 99.6% (A), 93.1% (B), 83.8% (C), and 88.8% (D) had an adequate response . Spike -specific T cell responses were detected in almost half of the suboptimal and non -responders. No new safety signals were observed [36]. 1.7 Third vaccination Although most patients with solid tumors develop an adequate SARS -CoV-2-binding antibody response after vaccination, 6.9%, 16.2%, and 11.2% of patients treated with immunotherapy, chemotherapy, and chemo -immunotherapy, respectively, are still suboptimal or non-responders. As most of them show an increase in antibody concentration after the second vaccination, an additional third vaccination might turn them into adequate responders. In the extension of the VOICE tria l, we will investigate whether non and suboptimal responders might benefit from a third vaccination. We will study whether an additional mRNA -1273 administration can improve the antibody response of participants in the VOICE trial who had a low antibody response on day 28 following two mRNA -1273 vaccinations. In addition safety, neutralizing antibodies and SARS -CoV-2 Spike -specifi c interferon -gamma T cell response will be studied. 1.8 Current vaccination strategy in the Netherlands Since October 2021, all patients with cancer who received chemotherapy and/or immunotherapy during or within 3 months before their first vaccination received an invitation for a third vaccination with an mRNA vaccine as part of their primary vaccination . This applies to all patients in the VOICE trial who did not receive a third vaccination within the study. Furthermore, everyone is entitled to receive a booster vaccination with an mRNA vaccine at least 3 months after completion of the primary vaccination, whether that consisted Version number: 6.0, 27 December 2021 17 of 49 of 2 or 3 vaccinations. This means that the majority of the study participants will have had extra vaccinations at different time points by January 2022. Therefore, we will implement 2 cross sectional measurements at 11 and 18 months after the second vaccination (in February and September 2022) and record the date and type of those extra vaccinations retrospectively. This will provide insight in the immune status against COVID -19 of cancer patients in the Netherlands compared to a coh ort without cancer in 2022. Version number: 6.0, 27 December 2021 18 of 49 2. OBJECTIVES Primary Objective:  To assess the antibody based immune response after vaccination against COVID -19 in patients with cancer treated with immunotherapy and/or chemotherapy as compared to controls Secondary Objectives :  To assess adverse events (AEs) after vaccination against COVID -19 in patients with cancer treated with immunotherapy and/or chemotherapy  To assess durability of the antibody response in patients with cancer treated with immunotherapy and/or chemotherapy  To analyze the SARS -CoV-2 specific T cell response after vaccination in patients with cancer treated with immunotherapy and/or chemotherapy Exploratory Objectives:  To perform in -depth analysis of cell ular immune response s in patients with cancer treated with immunotherapy and/or chemotherapy  To identify baseline (immune) parameters associated with vaccination response in patients with cancer treated with immunotherapy and/or chemotherapy  To assess the neutralizing capacity of antibodies aga inst SARS -CoV-2 after vaccination in patients with cancer treated with immunotherapy and/or chemotherapy  To analy ze induction of mucosal antibodies against SARS -CoV-2 in mucosal lining fluid samples . To describe the incidence of SARS -CoV-2 infection , outcome of COVID -19 during 12 months after vaccination in patients with cancer treated with immunotherapy and/or chemotherapy  To analyze SARS -CoV-2-binding antibody concentration after a third vaccination in participants without an adequate antibody respon se after two vaccinations  To analyze safety of a third vaccination Version number: 6.0, 27 December 2021 19 of 49 3. STUDY DESIGN This i s a prospective multicenter cohort study , designed to evaluate the immune response and safety after vaccination against COVID -19 in three cohorts with cancer patient s and one cohort of participants without cancer (see Fig.1) . The patient cohorts are defined by type of cancer treatment . Immunotherapy, chemotherapy and chemo -immunotherapy were chosen because these treatment regimens may affect the efficacy and safety of vaccination against COVID -19 in different ways. Figure 1. Trial design To reflect the real -world population of patients with cancer treated with immunotherapy and/or chemotherapy, this trial is designed as inclusive as possible. Exclusion criteria are minimal and serve to exclude patients who are not evaluable , or in whom vaccination is considered not safe or not effective. A cohort of volunteers without a cancer diagnosis is included for comparison. Because a ge is an important predictor of the abi lity to mount an effective immune response to vaccination [37], partners of patients are enrolled in cohort A . We will take care that from all patient cohorts partners are approached, until cohort A is complete. We anticipate that accrual of cohort A will be completed earlier than the patient cohorts. All participants will receive two vaccination s against COVID -19 according to standard of care . Participants with an inadequate antibody response will be offered a third vaccination. To assess immune response s after vaccination, blood samples will be collected at baseline (i.e. Version number: 6.0, 27 December 2021 20 of 49 prior to first vaccination ), at the day of the second (and if applicable the third) vaccination and at day 28 after the second and third vaccination and 6 , 11 and 18 months after the second vaccination by venipuncture . To evaluate hematology, with or without liver and kidney function, additional blood samples will be collected at baseline, at the day of the second and third vaccination, and at day 28 after the second and thi rd vaccination and 6 , 11 and 18 months after the second vaccination. Nasal m ucosal lining fluid will be collected at baseline and at day 28 after the second vaccination according to a non -invasive sampling method. To evaluate vaccination related AEs, patients will be asked to collect solicited local and systemic AEs for 7 days after each vaccination using a questionnaire . Similarly serious AEs (SAEs) will be collected for 7 days after each vaccination. Most patients who receive systemic cancer treatment experience multiple AEs that are cancer treatment related , or disease related. As vaccination related AEs are mainly expected within the first week after vaccination , it is not useful to collect all AEs for a prolonged period . Ins tead, all newly occurring immune related AEs (ir AEs) are collected for the immunotherapy and chemo - immunotherapy cohorts (B and D) up to 28 days after the second and if applicable the third vaccination . irAEs are toxicities from immune checkpoint inhibitors and do not include infus ion reactions [ 38]. Furthermore , adverse events of special interest (AESI s) will be collected for the duration of the study in the patient cohorts . Information on incidence of SARS -CoV-2 infection , outcome of COVID -19 during 18 months after the second vaccination will be collected using questionnaires. For the study participants who give separate consent, information on positive corona tests during the study will also be collected from the RIVM . Although this study is not powered to detect differences in protection against COVID -19 between patients and control s, information on incidence of SARS -CoV-2 infection, outcome of COVID -19 will be collected up to 18 months after the second vaccination for descriptive purposes . 4. STUDY POPULATI ON 4.1 Population (base) 4.2 Inclusion criteria To be eligible to participate in this study, a subject must meet all of the following criteria:  Age of 18 years or older  Life expectancy > 12 months  Ability to provide informed consent Version number: 6.0, 27 December 2021 21 of 49 Additional criteria for cohort A:  Partner of a participating patient Addition al criteria for cohort B:  Histologic al diagnosis of a solid malignancy  Treatment with monotherapy immune checkpoint inhibitor (ICI) against Programmed Death 1 (PD1) or its ligand PD -L1 (in curative or non -curative setting)  Last ICI administration within 3 months of vaccination Addition al criteria for co hort C:  Histologic al diagnosis of a solid malignancy  Treatment with cytotoxic chemotherapy (monotherapy and combination chemotherapy is allowed, as well as a combination with radiotherapy, in curative or non -curative setting)  Last chemotherapy administration within 4 weeks of vaccination Addition al criteria for cohort D:  Histologic al diagnosis of a solid malignancy  Treatment with a PD1 or PD -L1 antibody in combination with cytotoxic chemotherapy (in curative or non -curative setting)  Last chemotherapy administration within 4 weeks of vaccination  Last ICI admi nistration within 3 months of vaccination 4.3 Exclusion criteria A potential subject who meets any of the following criteria will be excluded from participation in this study:  Confirmed SARS -CoV-2 infection (current or previous)  Women who are pregnant or breastfeeding  Active hematologic malignancy  Any i mmune deficiency not related to cancer or cancer treatment (e.g. inherited immune deficiency or known infection with Human Immunodeficiency Virus)  Systemic treatment with corticosteroids (> 10 mg daily p rednisone equivalent) or other immunosuppressive medication within 14 days of vaccination.