Reducing Patient Time Burden in HER2+ Breast Cancer with Subcutaneous Trastuzumab/Pertuzumab 

In early-stage HER2-positive (HER2+) breast cancer, the delivery route of trastuzumab and pertuzumab (HP) is emerging as more than a matter of convenience—it may be a key determinant of patient quality of life and infusion center efficiency.

Findings from a time and motion substudy within the phase II ADEPT trial provide prospective evidence supporting subcutaneous (SC) administration of HP as a meaningful improvement in time burden over traditional intravenous (IV) infusion.

Study Design Highlights: Inside the ADEPT Time and Motion Substudy

This crossover substudy prospectively enrolled 22 patients participating in the ADEPT trial, which investigates adjuvant SC HP with endocrine therapy in hormone receptor-positive, HER2-positive stage I breast cancer (pT1N0 or pT1N1mi). Each patient received two cycles of IV HP followed by two cycles of SC HP, enabling direct intra-patient comparisons. Researchers captured time points related to drug preparation, administration, and patient experience using real-time electronic medical records and nursing flowsheets.

The primary endpoint was total time spent in the treatment chair, with secondary endpoints assessing total patient treatment time and pharmacy workflow efficiency.

Efficiency Gains: By the Numbers

SC administration offered clear time-saving advantages across all measured outcomes:

• Treatment Chair Time: Patients spent 61.8 fewer minutes in the chair with SC HP versus IV (22.5 versus 84.3 minutes; P < .0001)
• Overall Patient Time in Clinic: Each visit was 81.8 minutes shorter (96 versus 177.8 minutes; P < .0001)
• Pharmacy Workflow: Prep and verification times dropped by 78.2 minutes (41 versus 119.2 minutes; P < .0001)
• Drug Administration Alone: Cut from 61.6 minutes (IV) to just 7.4 minutes (SC; P < .0001)

Cumulatively, these reductions recover substantial time over a year of adjuvant therapy for both patients and care teams.

Why Time Matters: Tackling “Time Toxicity”

Time toxicity—the cumulative burden of treatment time—has emerged as a critical but underrecognized factor in patients’ quality of life. Even modest per-visit time savings, extrapolated over 12 months, can reclaim several days of a patient’s life otherwise spent in clinic.

SC delivery may also ease psychosocial and work-related disruptions. For patients balancing employment, caregiving, or chronic conditions, reducing treatment session time by over an hour is a meaningful shift.

Examining Health System Efficiency

In addition to quality-of-life benefits, SC HP may also deliver operational advantages:

• Faster drug prep eases pharmacy workload
• Shorter chair times improve infusion center throughput
• Nurses can redirect time to more complex care needs

These workflow efficiencies align with findings from similar studies of SC rituximab and daratumumab that enabled more patients to be treated daily without expanding resources.

The Next Frontier: At-Home Potential

Though this analysis focused on in-clinic delivery, SC formulations could offer the potential of home-based care. Preliminary safety data from U.S. and European pilots are promising, though barriers like staffing and self-injection logistics remain.

Additionally, cost-effectiveness analyses are mixed. While IV biosimilars may appeal to payers, broader analyses incorporating caregiver burden, travel, and productivity often reveal SC’s systemic value.

Clinical Takeaway

In this time and motion substudy from the ADEPT trial, SC HP meaningfully reduces treatment time for patients and providers without compromising efficacy. As care models evolve to prioritize convenience and patient experience, SC delivery may emerge as a preferred option for eligible patients receiving HER2-directed adjuvant therapy.

Ongoing research into broader real-world implementation could further shift treatment strategies toward a model that values not only survival—but also in treatment experience.

Reference:
Waks AG, Chen EL, Graham N, et al. Subcutaneous vs Intravenous Trastuzumab/Pertuzumab: A Time and Motion Substudy of a Phase II Trial of Adjuvant Trastuzumab/Pertuzumab for Stage I HER2+ Breast Cancer (ADEPT trial). JCO Oncol Pract. 2025;21(3):351-357. doi:10.1200/OP.24.00021