SABRE: A Single-arm Prospective Study Measuring Safety and Tolerability of SARS-CoV-2 Neutralising Antibodies in High-risk Populations

Inclusion Criteria: * Aged ≥18 years old at screening; * Able to give informed written consent including consent to long-term follow-up; * Willing and able to comply with visit schedule and provide blood sampling; * Have received at least two doses of a routine NHS standard of care SARS-Cov-2 vaccine and do not have detectable serum SARS-CoV-2 anti-spike antibodies in routine NHS assays \> two weeks post 2nd vaccination, including: 1. Solid organ transplant recipients; 2. People with specific haematological diseases; 3. People undergoing active chemotherapy, having immunotherapy or other continuing antibody or targeted therapy that affect immune system; 4. People with cancers of the blood or bone marrow such as leukaemia, lymphoma or myeloma who are at any stage of treatment; 5. People who have had bone marrow or stem cell transplants in the last 6 months or who are still taking immunosuppression drugs; 6. People who are receiving long-term immune suppression therapy for ny other condition * Be ineligible to receive a SARS-CoV-2 prophylactic vaccine for any of the following reasons: 1. The need to commence immediate systemic chemotherapy; 2. The need to receive a bone-marrow and therefore the requirement to initiate profound immune suppression * Have an estimated life expectancy of \> 12 weeks; * Females capable of becoming pregnant\* must agree to use hormonal contraception, intrauterine device, intrauterine hormone-releasing system, or to complete abstinence\*\* from at least four weeks before the first antibody injection and for 20 months after the last antibody injection * Females capable of becoming pregnant are defined as: fertile, following menarche and until becoming post-menopausal unless permanently sterile. Permanent sterilisation methods include hysterectomy, bilateral salpingectomy and bilateral oophorectomy. A postmenopausal state is defined as no menses for 12 months without an alternative medical cause. A high follicle stimulating hormone (FSH) level in the postmenopausal range may be used to confirm a post-menopausal state in women not using hormonal contraception or hormonal replacement therapy. However, in the absence of 12 months of amenorrhea, a single FSH measurement is insufficient. \*\*Complete abstinence (defined as refraining from heterosexual intercourse) must be in line with the preferred and usual lifestyle of the participant. Barrier contraception, periodic abstinence (e.g. calendar, ovulation, symptothermal, postovulation methods), withdrawal and progestogen-only oral hormonal contraception where inhibition of ovulation is not the primary mode of action are not acceptable methods of contraception. Exclusion Criteria: * Current SARS-CoV-2 infection confirmed by SARS-CoV-2 RT-PCR positive result from nasopharyngeal swab within the past 10 days and up to 24 hours prior to enrolment; * Participation in any other clinical trial of an experimental agent or any non-interventional study where additional blood draws are required; participation in observational studies is permitted. Patients in survival follow up of another clinical trial of an investigational medicinal product (CTIMP) study may be considered if more than 5 half lives have passed since last CTIMP treatment and with permission of the medical monitor for the other study; * History of anaphylaxis or severe adverse reaction to antibody injections, or hypersensitivity to neutralising antibodies or to any constituent products or excipients thereof; * Treatment with intravenous immunoglobulin (IVIG) or other investigational treatments planned during the duration of the trial; * Clinically significant abnormal blood test results at screening including: 1. Moderate to severe hepatic impairment as defined by Child-Pugh classification; 2. ALT \>5 x ULN; 3. INR \>1.5 * Pregnancy or breastfeeding