Self-Amplifying mRNA COVID-19 Vaccine (LUNAR-COV19) Versus Comirnaty Vaccine in Adult Hematopoietic Cell Transplant Patients

This phase IIb trial compares the effect of LUNAR-COV19 vaccine to Comirnaty vaccine in treating adult patients who have received a hematopoietic cell transplant (HCT). Guidelines recommend repeating severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) vaccination of 3 messenger ribonucleic acid (mRNA) vaccines followed by a fourth booster 3-6 months after treatment. However, vaccination is less effective in HCT patients compared to healthy people due to impaired immune responses. LUNAR-COV19, a self-amplifying mRNA vaccine, may help the body's own immune system recognize the SARS-CoV-2 spike protein and fight the virus by using a special mRNA that copies itself for a stronger response. Vaccines made from mRNA with SARS-CoV-2, such as Comirnaty, may help the body build an effective immune response. This may provide active protection against SARS-CoV-2 infection. LUNAR-COV19 may be safe and tolerable and may generate a better and more durable immune response than the Comirnaty vaccine in adult patients who have received a HCT.

OUTLINE: Patients are randomized to 1 of 2 arms. ARM I: Patients receive LUNAR-COV19 intramuscularly (IM) on days 1, 29 and 113 in the absence of medical conditions or unacceptable toxicity. Additionally, patients undergo nasal swab at screening and at time of suspected SARS-CoV-2 infection, as well as blood sample collection throughout the study. ARM II: Patients receive SARS-CoV-2 Comirnaty IM on days 1, 29 and 113 in the absence of medical conditions or unacceptable toxicity. Additionally, patients undergo nasal swab at screening and at time of suspected SARS-CoV-2 infection, as well as blood sample collection throughout the study. After completion of study treatment, patients are followed up at days 115, 120, 127, 141 and 281.