Subcutaneous injection of trastuzumab into the thigh versus abdominal wall in patients with HER2-positive early breast cancer: Pharmacokinetic, safety and patients' preference - Substudy of the randomised phase III GAIN-2 study

BACKGROUND

Trastuzumab given intravenously in combination with chemotherapy is standard of care for patients with early HER2-positive breast cancer (BC). Different randomised studies have shown equivalent efficacy of a subcutaneous injection into the thigh compared to the intravenous formulation. Other body regions for injection have not been investigated but might be more convenient for patients.

METHODS

After surgery, patients were randomised to receive either subcutaneous trastuzumab into the thigh or into the abdominal wall (AW). Patient preferences were evaluated using validated questionnaires (PINT). Primary objectives of this multicentre, non-blinded, randomised substudy of the GAIN-2 study were to investigate pharmacokinetics of the injection into the thigh versus AW and to determine patients' preferences of either administration site versus the previously received intravenous application.

RESULTS

226 patients were randomised and 219 patients (thigh: N = 110; AW: N = 109) formed the modified intent-to-treat (mITT). Overall, 83.5% (out of N = 182 with information about patients' preference) preferred subcutaneous over previous intravenous application or had no preference. Preference was similar between both administration sites (thigh: 80.6%; AW: 86.5; p = 0.322). Pharmacokinetic analysis included 30 patients. Geometric means of C_max and AUC_0-21d were higher in thigh than in AW group (geometric mean ratio with body weight adjustment: C_max: 1.291, 90%-CI 1.052-1.584; AUC_0-21d: 1.291, 90%-CI 1.026-1.626). Safety profile was in line with previous reports of subcutaneous trastuzumab.

CONCLUSION

Subcutaneous trastuzumab into the thigh showed an approximately 30% higher bioavailability. Injections were well tolerated and preferred over intravenous administration. The subcutaneous injection into the thigh should remain the standard of care.

Phase III randomised trial comparing intense dose-dense chemotherapy to tailored dose-dense chemotherapy in high-risk early breast cancer (GAIN-2)

BACKGROUND

The GAIN-2 trial was designed to identify a superior intense dose-dense (idd) strategy for high-risk patients with early breast cancer. Here, we report an interim analysis, at which the predefined futility boundary was crossed.

PATIENTS AND METHODS

GAIN-2 was an open-label, randomised, multicentre phase III trial. Two thousand eight hundred and eighty seven patients were randomised 1:1 between three courses each of idd epirubicin (E) 150 mg/m², nab-paclitaxel (nP) 330 mg/m² and cyclophosphamide (C) 2000 mg/m² (iddEnPC) versus four cycles of leucocyte nadir-based tailored and dose-dense EC (dtEC) followed by four cycles of tailored and dose-dense docetaxel (dtD) (dtEC-dtD).

RESULTS

The duration of median follow-up was 45.8 (range 0.0-88.3) months. Trial objectives included invasive disease-free survival (iDFS) as the primary end-point. A total of 593 patients received the treatment as neoadjuvant chemotherapy. At the time of futility interim analysis, 414 events for iDFS were reported. Overall, there was no difference in iDFS between iddEnPC and dtEC-dtD with 4-year iDFS rates of 84.3% (95% confidence interval (CI) 82.0-86.4%). Among all predefined subgroups, hormone receptor-positive and human epidermal growth factor receptor 2-negative (HR+/HER2-), lobular cancer and ≤50 years subgroups predicted for better iDFS in the dtEC-dtD arm. Overall, 88.1% of patients completed all treatment in both arms. Haematological toxicity grade 3/4 and grade 3/4 non-haematological adverse events were significantly higher with iddEnPC (iddEnPC 50.8% vs dtEC-dtD 45.1%, P = 0.002), especially arthralgia and peripheral sensory neuropathy. Two treatment-related deaths occurred during dtEC-dtD, corresponding to a low mortality rate of 0.07%.

CONCLUSIONS

iDFS is equal in both regimens, but tailoring dose-dense chemotherapy improved outcomes in HR+/HER2-, lobular cancer and patients ≤50 years.

GAIN-2: Neo-/adjuvant phase III trial to compare intense dose-dense chemotherapy (CT) to tailored dose-dense CT in patients (pts) with high risk early breast cancer (EBC): Results on safety and interim invasive disease-free survival (iDFS)

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Background: GAIN-2 (NCT01690702) compared efficacy and safety of intense, dose-dense epirubicin, nab-paclitaxel, and cyclophosphamide (iddEnPC) vs dose-dense, dose-tailored epirubicin/ cyclophosphamide followed by dose-dense, dose-tailored docetaxel (dtEC-dtD) as adjuvant or neoadjuvant CT for node-positive or high risk node-negative EBC. Here, we report safety results and interim analysis (IA) of the primary endpoint iDFS. Methods: Pts (luminal A ≥N2; luminal B N+; HER2+ and TNBC) were randomized between iddEnPC (E 150 mg/m2, nP 330 mg/m2, C 2000 mg/m2, all q2w x 3) or dtEC-dtD (dtEC q2w x 4 followed after 1 week rest by dtD q2w x 4). Primary objective was to compare iDFS. 797 events are needed to detect a hazard ratio of 0.819 with a 2-sided log-rank-test with 80% power and α=0.05. The IA of iDFS was planned after 50% of the events have occurred. Safety and compliance were secondary objectives. Results: Between 10/2012 and 09/2018, 2887 pts were randomized and 2857 started treatment (iddEnPC 1429; dtEC-dtD 1428). Median age was 51 (range 18-75) years. Overall, 18.1% were luminal A, 31.5% luminal B/HER2-, 18.8% hormone-receptor (HR)+/HER2+, 8.5% HR-/HER2+ and 23.2% TNBC. Overall, 88.1% of pts completed all treatment in both arms. 66.8% with iddEnPC vs 58.8% with dtEC-dtD delayed CT dose (p<0.001). Grade 3-4 non-hematological adverse events (AEs) were more frequent with iddEnPC (iddEnPC 50.8% vs dtEC-dtD 45.1%, p=0.002). Grade 3-4 leukopenia, neutropenia, febrile neutropenia, arthralgia, and peripheral sensory neuropathy were significantly higher with iddEnPC. There were 1464 serious AEs (iddEnPC 870 vs dtEC-dtD 594) and 26 (9 vs 17) predefined AEs of special interest (anaphylaxis, any AE affecting cranial nerves, macula edema). Two deaths occurred during dtEC-dtD. After a median follow-up of 45.8 months, there was no difference in iDFS between arms (log-rank p=0.9102, hazard ratio iddEnPC vs dtEC-dtD 1.01, 95% CI 0.83-1.23). Conclusions: No new safety concerns were observed. Use of both iddEnPC and dtEC-dtD appears feasible in the (neo)adjuvant treatment of high risk EBC. Clinical trial information: NCT01690702 .

Development and validation of a novel prognostic score to predict survival in patients with metastatic colorectal cancer: the metastatic colorectal cancer score (mCCS)

AIM

Published prognostic scores for metastatic colorectal cancer (mCRC) are based on data from highly selected patient subgroups with specified first-line treatments and may not be applicable to routine practice. We have therefore developed and validated the metastatic colorectal cancer score (mCCS) to predict overall survival (OS) for patients with mCRC.

METHOD

A total of 1704 patients from the prospective, multicentre cohort study Tumour Registry Colorectal Cancer were separated into learning (n = 796) and validation (n = 908) samples. Using a multivariate Cox regression model, the six-factor mCCS was established.

RESULTS

The six independent prognostic factors for survival are as follows: two or more metastatic sites at the start of first-line treatment, tumour grading ≥ G3 at primary diagnosis, residual tumour classification ≥ R1/unknown, lymph node ratio (of primary tumour) ≥ 0.4, tumour stage ≥ III/unknown at primary diagnosis and KRAS status mutated/unknown. The mCCS clearly separated the learning sample into three risk groups: zero to two factors (low risk), three factors (intermediate risk) and four to six factors (high risk). The prognostic performance of the mCCS was confirmed in the validation sample and additionally stratified a large sample of patients with known (K)RAS mutation status.

CONCLUSION

The novel prognostic score, mCCS, clearly defines three prognostic groups for OS at start of first-line therapy. For oncologists, the mCCS represents a simple and easy-to-apply tool for routine clinical use, as it is based on objective tumour characteristics and can assist with treatment decision-making and communication of the prognosis to patients.

[Hand and foot purpura ("glove and sock" syndrome) caused by parvovirus B19 infection]

After a period of general nonspecific symptoms (weakness; nocturnal sweating) for a few days a 29-year-old man suddenly developed a purpura-like rash on both hands and feet ("glove and sock") with mild itching and oedema. A blood count demonstrated leukopenia (2100/microliters) with neutropenia (1100/microliters), thrombocytopenia (81,000/microliters) and reticulocytopenia (1/1000), while haemoglobin content was normal. The bone-marrow showed almost complete reduction of erythropoiesis with the presence of giant proerythroblasts. Granulopoiesis and megakaryopoiesis were unremarkable. Positive tests for IgM and IgG antibodies against parvovirus B19 established the diagnosis of infection with this organism. The rash, blood picture and bone-marrow changes all regressed spontaneously, without any treatment, within a week. The petechial or purpuric "glove and sock" syndrome may be a special form of parvovirus B19 infection.