Is weight-based IV dosing of trastuzumab preferable to SC fixed-dose in some patients? A systematic scoping review.

Trastuzumab, a key treatment for HER2-positive breast cancer, is available in weight-based IV and fixed-dose (600 mg) SC formulations. While the Phase 3 HannaH trial indicated non-inferiority of the SC formulation, there is some concern that the target plasma concentration may not be reached in overweight/obese patients whereas low-body-weight patients may be at risk of toxicity. This scoping review evaluated whether overweight/obese patients are at risk of below-target exposure with fixed-dose SC trastuzumab, whether low-body-weight patients are at risk of increased toxicity, especially cardiotoxicity, and whether IV and SC trastuzumab are equivalent in terms of treatment-emergent adverse events (TEAEs) (e.g. infections). Thirty-seven publications that met the eligibility criteria were included. Body weight is not an important determinant of exposure to trastuzumab at steady state (i.e. pre-dose cycle 8); however, real-world evidence suggests that the target concentration (20 µg/mL) may not be reached with the first SC dose in overweight/obese patients. There is no evidence that low-body-weight patients are at increased risk of cardiotoxicity with SC trastuzumab, although this may be confounded by the higher rate of cardiovascular comorbidities in overweight patients. In Phase 3 trials, SC trastuzumab was associated with higher rates of ISRs, ADAs and SAEs, the latter often requiring hospitalization and occurring during adjuvant treatment when patients are not burdened by chemotherapy. The route of administration of trastuzumab (IV vs SC) in different treatment settings should be discussed with the patient, taking into account the risks and benefits associated with each route.

The clinical and cost-effectiveness of supplemental parenteral nutrition in oncology.

BACKGROUND: Clinical guidelines recommend that parenteral nutrition (PN) is added to enteral nutrition (EN; supplemental parenteral nutrition (SPN)) in order to meet energy and protein needs in patients with cancer when EN alone is insufficient. However, although cancer-related malnutrition is common, there is poor awareness of the value of nutritional care, resulting in SPN being chronically underused. METHODS: We performed a targeted literature review and exploratory cost-utility analysis to gather evidence on the clinical effectiveness of SPN, and to estimate the potential cost-effectiveness of SPN versus EN alone in an example cancer setting. RESULTS: The literature review identified studies linking SPN with malnutrition markers, and studies linking malnutrition markers with clinical outcomes. SPN was linked to improvements in body mass index (BMI), fat-free mass, phase angle (PhA) and prealbumin. Of these markers, BMI and PhA were strong predictors of survival. By combining published data, we generated indirect estimates of the overall survival HR associated with SPN; these ranged from 0.80 to 0.99 (mode 0.87). In patients with Stage IV inoperable pancreatic cancer, the incremental cost-effectiveness ratio versus EN alone was estimated to be £41 350 or £91 501 depending on whether nursing and home delivery costs for EN and SPN were combined or provided separately. CONCLUSION: Despite a lack of direct evidence, the results of the literature review demonstrate that SPN may provide important clinical and quality of life benefits to patients with cancer. The potential for any improvement in outcomes in the modelled patient population is very limited, so cost-effectiveness may be greater in patients with less severe disease and other types of cancer.

Review and comparison of clinical evidence submitted to support European Medicines Agency market authorization of orphan-designated oncological treatments.

BACKGROUND: Clinical trials for treatments indicated for orphan diseases may be limited due to the low prevalence of such diseases; this can result in implications for both regulatory and health economic perspectives. This study assessed the pivotal clinical evidence packages submitted to support applications for European Medicines Agency (EMA) marketing authorizations for treatments for orphan conditions, in relation to the size of the eligible patient population. METHODS: Approved treatments for EMA-designated orphan conditions (defined as life-threatening or chronically debilitating conditions that affect ≤5/10,000 people) were identified from the EMA web site. All treatments reviewed were included in anatomical therapeutic chemical (ATC) category L (antineoplastic and immunomodulating drugs): this category was selected because it is the largest ATC category, containing almost 50% of all approved orphan-designated products. Treatments were reviewed if they had been approved within the past 7 years and had been evaluated in a controlled trial using at least one survival-based clinical endpoint. Treatments were compared in terms of patient-years (accumulated duration of follow-up), the number of patients in the pivotal trials and disease prevalence. RESULTS: As of 1 February 2014, 68 treatments had been approved for orphan-designated conditions, of which 30 belonged to ATC category L and 14 met all inclusion criteria. The number of patients in the pivotal trials ranged from 162 to 846 (median 485). In terms of patient-years, the longest duration of follow-up was seen in the pivotal trial of mifamurtide in osteosarcoma, which had 4068 patient-years; excluding this trial, follow-up ranged from 308 to 2906 patient-years (median 1796 years). Osteosarcoma had the second smallest eligible patient population (0.5/10,000 persons) of the reviewed treatments. CONCLUSIONS: Clinical trials of orphan treatments are often limited by low patient numbers and inadequate follow-up. Pooling of expertise in single centres and the establishment of rare disease reference networks and patient registries may facilitate appropriate trial design for orphan-designated treatments. This analysis found that the pivotal clinical trial for mifamurtide in osteosarcoma had the largest number of patient-years of follow-up, despite a small eligible patient population, showing that it is possible to conduct studies with an adequate patient population size and duration of follow-up in patient-years, and a comparative design with clinical, survival-based, endpoints.