Caregivers (i.e., family and friends) of patients with cancer are essential in providing care during cancer treatment. For patients who are undergoing a hematopoietic stem cell transplant/transplantation (HSCT) as treatment for their cancer, caregivers are even more crucial before, during, and after their transplantation. Although HSCT is potentially curative for some patients with blood cancers, the treatment is intensive and accompanied by a prolonged hospitalization as patients recover from the toxic side-effects of chemotherapy and medical complications from the transplantation. Unsurprisingly, during the entire transplantation process, caregiver burden is high as caregivers witness and support their loved ones through multiple treatment-related complications, management of ongoing physical symptoms, and complex medication schedules. Caregiver burden leads to poor health outcomes including poor caregiver quality of life, fatigue, depression, anxiety, impaired physical health, and low levels of resilience and positive emotions. Reducing distress and enhancing positive emotions can both reduce caregiver burden and improve caregiver quality of life. However, the few interventions in the HSCT caregiver population have mostly focused on mitigating distress, despite strong evidence that enhancing positive emotions in caregivers reduces caregiver burden and promotes physical and psychological health. To address this gap, we hope to develop and test an intervention that emphasizes positive emotions in caregivers of HSCT recipients. A scalable and accessible positive emotion-based intervention tailored to the unique needs of HSCT recipients' caregivers provides a new line of behavioral intervention resources that could offer benefit to both caregivers and patients and could be generalizable to other cancer caregivers.

The proposed project (PATH-C) entails two phases:

1. Phase one is an open-pilot trial in 5 caregivers of patients undergoing HSCT to refine the PATH intervention.
2. Phase two is single-arm open-pilot trial evaluating the feasibility and acceptability of the PATH intervention in 20 caregivers of patients undergoing HSCT.

All participants will be approached in-person at the routine HSCT patient consent clinic visit or, with patient permission, over the phone if the caregiver is not physically present at the consent visit for eligibility determination. Interested participants will be screened based on the inclusion/exclusion criteria and verbal consent will be obtained.

Upon consent to participate in the study, participants in both phases will be asked to complete baseline questionnaires either in-person, over the phone, or via a REDCap survey link to participants. After baseline assessments are completed, participants will be given an intervention manual with 9-weekly positive psychology (PP) exercises and an explanation of the exercises and intervention.

All participants in Phases 1 and 2 will be asked to complete the 9-weekly PP exercises starting after the baseline questionnaires (i.e., after the patient transplant consent visit) are completed in the pre-transplant phase and to speak with the study interventionist, a trained clinical research coordinator (CRC), weekly. Immediately after the completion of each exercise, participants will rate the ease of exercise completion, overall utility of the exercise, and their current levels of positive affect. After the Week 9 intervention phone session, all participants in both phases will complete another set of self-assessment questionnaires either over the phone, in-person at a routine clinic visit, or via a REDCap survey link emailed to participants. Additionally, participants will be asked to complete a recorded exit interview over the phone. These individual, semi-structured exit interviews will elicit feedback about the intervention (e.g., relevance and applicability of the chosen PP exercises, intervention length, timing, and delivery), study procedures, and questionnaires. Exit interviews will be recorded, transcribed, coded and thematically analyzed. At study completion, we will inquire about participants' potential interest in being contacted about our future studies.

Inclusion Criteria:

• Adult caregivers (≥18 years) of patients undergoing allogeneic hematopoietic stem cell transplant (HSCT) at Dana-Farber Cancer Institute (DCFI).
• A relative or a friend who either lives with the patient or has in-person contact with him or her at least twice per week and is identified as the primary caregiver for HSCT.
• Ability to speak English and able to complete questionnaires with minimum assistance of an interpreter.

Exclusion Criteria:

• Cognitive deficits impeding a caregiver's ability to provide informed consent or participate adequately in the study assessed via a commonly used 6-item cognitive assessment, the Brief Interview for Mental Status (BIMS) screening tool, which is sensitive and specific for screening for cognitive impairment in research subjects.

The Dana-Farber/Harvard Cancer Center encourages and supports the responsible and ethical sharing of data from clinical trials. De-identified participant data from the final research dataset used in the published manuscript may only be shared under the terms of a Data Use Agreement. Requests may be directed to Sponsor, Investigator, or designee. The protocol and statistical analysis plan will be made available on ClinicalTrials.gov only as required by federal regulation or as a condition of awards and agreements supporting the research.

Data can be shared no earlier than 1 year following the date of publication

Contact the study investigator at hermioni_amonoo@dfci.harvard.edu

Baseline data is reported for participants who completed follow-up measures and exit interviews

Treatment-related and non-treatment related adverse event data were collected during the active study period, which lasted from study enrollment through follow-up assessment completion (week 9). Because this was a supportive care intervention, adverse events were not assessed at a pre-specified time. Instead, adverse events were recorded as reported by study participants during the active study period.

Treatment-related and non-treatment related adverse event data that were related to study procedures were reported to the Institutional Review Board (IRB) at the PI's discretion. Participants requesting withdrawal from the study were asked to provide reasons for withdrawal to monitor for adverse events or unanticipated events related to study procedures.