3-year invasive disease-free survival with chemotherapy de-escalation using an 18F-FDG-PET-based, pathological complete response-adapted strategy in HER2-positive early breast cancer (PHERGain): a randomised, open-label, phase 2 trial

BACKGROUND

PHERGain was designed to assess the feasibility, safety, and efficacy of a chemotherapy-free treatment based on a dual human epidermal growth factor receptor 2 (HER2) blockade with trastuzumab and pertuzumab in patients with HER2-positive early breast cancer (EBC). It used an 18fluorine-fluorodeoxyglucose-PET-based, pathological complete response (pCR)-adapted strategy.

METHODS

PHERGain was a randomised, open-label, phase 2 trial that took place in 45 hospitals in seven European countries. It randomly allocated patients in a 1:4 ratio with centrally confirmed, HER2-positive, stage I-IIIA invasive, operable breast cancer with at least one PET-evaluable lesion to either group A, where patients received docetaxel (75 mg/m2, intravenous), carboplatin (area under the curve 6 mg/mL per min, intravenous), trastuzumab (600 mg fixed dose, subcutaneous), and pertuzumab (840 mg loading dose followed by 420 mg maintenance doses, intravenous; TCHP), or group B, where patients received trastuzumab and pertuzumab with or without endocrine therapy, every 3 weeks. Random allocation was stratified by hormone receptor status. Centrally reviewed PET was conducted at baseline and after two treatment cycles. Patients in group B were treated according to on-treatment PET results. Patients in group B who were PET-responders continued with trastuzumab and pertuzumab with or without endocrine therapy for six cycles, while PET-non-responders were switched to receive six cycles of TCHP. After surgery, patients in group B who were PET-responders who did not achieve a pCR received six cycles of TCHP, and all patients completed up to 18 cycles of trastuzumab and pertuzumab. The primary endpoints were pCR in patients who were group B PET-responders after two treatment cycles (the results for which have been reported previously) and 3-year invasive disease-free survival (iDFS) in patients in group B. The study is registered with ClinicalTrials.gov (NCT03161353) and is ongoing.

FINDINGS

Between June 26, 2017, and April 24, 2019, a total of 356 patients were randomly allocated (71 patients in group A and 285 patients in group B), and 63 (89%) and 267 (94%) patients proceeded to surgery in groups A and B, respectively. At this second analysis (data cutoff: Nov 4, 2022), the median duration of follow-up was 43·3 months (range 0·0-63·0). In group B, the 3-year iDFS rate was 94·8% (95% CI 91·4-97·1; p=0·001), meeting the primary endpoint. No new safety signals were identified. Treatment-related adverse events and serious adverse events (SAEs) were numerically higher in patients allocated to group A than to group B (grade ≥3 62% vs 33%; SAEs 28% vs 14%). Group B PET-responders with pCR presented the lowest incidence of treatment-related grade 3 or higher adverse events (1%) without any SAEs.

INTERPRETATION

Among HER2-positive EBC patients, a PET-based, pCR-adapted strategy was associated with an excellent 3-year iDFS. This strategy identified about a third of patients who had HER2-positive EBC who could safely omit chemotherapy.

FUNDING

F Hoffmann-La Roche.

Palbociclib Rechallenge for Hormone Receptor-Positive/HER-Negative Advanced Breast Cancer: Findings from the Phase II BioPER Trial

PURPOSE

To assess the efficacy and exploratory biomarkers of continuing palbociclib plus endocrine therapy (ET) beyond progression on prior palbociclib-based regimen in patients with hormone receptor-positive/HER2-negative (HR+/HER2-) advanced breast cancer (ABC).

PATIENTS AND METHODS

The multicenter, open-label, phase II BioPER trial included women who had experienced a progressive disease (PD) after having achieved clinical benefit on the immediately prior palbociclib plus ET regimen. Palbociclib (125 mg, 100 mg, or 75 mg daily orally for 3 weeks and 1 week off as per prior palbociclib-based regimen) plus ET of physician's choice were administered in 4-week cycles until PD or unacceptable toxicity. Coprimary endpoints were clinical benefit rate (CBR) and percentage of tumors with baseline loss of retinoblastoma (Rb) protein expression. Additional endpoints included safety and biomarker analysis.

RESULTS

Among 33 patients enrolled, CBR was 34.4% [95% confidence interval (CI), 18.6-53.2; P < 0.001] and 13.0% of tumors (95% CI, 5.2-27.5) showed loss of Rb protein expression, meeting both coprimary endpoints. Median progression-free survival was 2.6 months (95% CI, 1.8-6.7). No new safety signals were reported. A signature that included baseline mediators of therapeutic resistance to palbociclib and ET (low Rb score, high cyclin E1 score, ESR1 mutation) was independently associated with shorter median progression-free survival (HR, 22.0; 95% CI, 1.71-282.9; P = 0.018).

CONCLUSIONS

Maintaining palbociclib after progression on prior palbociclib-based regimen seems to be a reasonable, investigational approach for selected patients. A composite biomarker signature predicts a subset of patients who may not derive a greater benefit from palbociclib rechallenge, warranting further validation in larger randomized controlled trials.

Challenging Endocrine Sensitivity of Hormone Receptor-Positive/HER2-Negative Advanced Breast Cancer with the Combination of Eribulin and Endocrine Therapy: The REVERT Study

BACKGROUND

Luminal advanced breast cancer (ABC) patients eventually progress on endocrine therapy. REVERT aimed to explore whether eribulin could restore endocrine sensitivity in a randomized, non-comparative phase II trial.

METHODS

Aromatase inhibitor (AI)-resistant patients with luminal ABC were randomized 1:1 to receive eribulin +/- AI. Patients were stratified by prior cyclin-dependent kinases 4/6 inhibitor (CDK4/6i) treatment. The primary endpoint was an investigator-assessed overall response rate (ORR) according to RECIST version 1.1 in the eribulin + AI arm. An interim analysis was planned with 11 evaluable patients according to a two-stage Simon design.

RESULTS

Twenty-two patients were enrolled (15 eribulin + AI arm; 7 eribulin arm). The trial was terminated early in March 2021, with eight (36.4%) patients still on treatment. ORR was 26.7% in the eribulin + AI arm (95% CI, 7.8-55.1%; p = 0.0541). In the eribulin arm, two (28.6%) patients had an objective response (95% CI, 3.7-71.0%). The difference between the study arms was not significant (p = 0.918). The addition of AI to eribulin also failed to show improvement in other efficacy endpoints. A significant interaction between the treatment arm and previous CDK4/6i treatment was observed for ORR (p = 0.018) and progression-free survival (p = 0.084). Overall, the toxicity profile was consistent with the known safety profile of eribulin. No treatment-related deaths were reported.

CONCLUSION

Eribulin + AI does not seem to improve outcomes compared with eribulin monotherapy in patients with AI-resistant luminal ABC. This chemo-endocrine approach deserves further investigation after progression to CDK4/6i-based therapy.

Palbociclib with Fulvestrant or Letrozole in Endocrine-Sensitive Patients with HR-Positive/HER2-Negative Advanced Breast Cancer: A Detailed Safety Analysis of the Randomized PARSIFAL Trial

BACKGROUND

Palbociclib has gained a central role in the treatment of hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer (ABC). Despite its manageable toxicity profile, venous thromboembolism (VTE) or interstitial lung disease (ILD)/pneumonitis may infrequently occur. Therefore, we provide a comprehensive summary of the safety and tolerability of the combination of endocrine therapy and palbociclib among patients included in the randomized phase 2 PARSIFAL study.

MATERIALS AND METHODS

Patients with endocrine-sensitive HR+/HER2- ABC and no prior therapy in an advanced setting (n = 486) were randomly assigned 1:1 to receive fulvestrant-palbociclib (FP) or letrozole-palbociclib (LP). Laboratory tests and the incidence of adverse events (AEs) were recorded at baseline and day 1 of each cycle. Progression-free survival (PFS) was estimated for patients with and without VTE.

RESULTS

A total of 483 patients were analyzed. Neutropenia, leukopenia, anemia, asthenia, arthralgia, fatigue, and diarrhea were the most frequent AEs in both groups. Febrile neutropenia occurred in 3 (1.2%) patients of the FP group and in 1 (0.4%) patient in the LP group. Six (2.5%; 0.4% grade 3) patients in the FP group and 6 patients (2.5%; 0.4% grade 3) in the LP group experienced ILD/pneumonitis. Pulmonary embolism was reported in 12 (5.0%) patients in the FP group and 6 (2.5%) patients in the LP group. Advanced age at baseline was the only factor significantly associated with an increased risk of pulmonary embolism (P < .01).

CONCLUSION

The PARSIFAL data confirmed the favorable safety profile of both palbociclib regimens. VTE and ILD/pneumonitis were occasionally reported, and their early detection allowed patients to continue treatment effectively without detriment to efficacy.

CLINICALTRIALS.GOV IDENTIFIER

NCT02491983; https://clinicaltrials.gov/ct2/show/NCT02491983).

High p16 expression and heterozygous RB1 loss are biomarkers for CDK4/6 inhibitor resistance in ER+ breast cancer

CDK4/6 inhibitors combined with endocrine therapy have demonstrated higher antitumor activity than endocrine therapy alone for the treatment of advanced estrogen receptor-positive breast cancer. Some of these tumors are de novo resistant to CDK4/6 inhibitors and others develop acquired resistance. Here, we show that p16 overexpression is associated with reduced antitumor activity of CDK4/6 inhibitors in patient-derived xenografts (n = 37) and estrogen receptor-positive breast cancer cell lines, as well as reduced response of early and advanced breast cancer patients to CDK4/6 inhibitors (n = 89). We also identified heterozygous RB1 loss as biomarker of acquired resistance and poor clinical outcome. Combination of the CDK4/6 inhibitor ribociclib with the PI3K inhibitor alpelisib showed antitumor activity in estrogen receptor-positive non-basal-like breast cancer patient-derived xenografts, independently of PIK3CA, ESR1 or RB1 mutation, also in drug de-escalation experiments or omitting endocrine therapy. Our results offer insights into predicting primary/acquired resistance to CDK4/6 inhibitors and post-progression therapeutic strategies.

Nobody dares stopping clinical research, not even COVID-19

In the global health emergency caused by the COVID-19, clinical trial management has proven to be critical for the pharmaceutical industry, sponsors, and healthcare professionals. Our experience as a sponsor managing interventional oncology clinical studies has provided us with some data and insights. Though limited by sample size, our data emphasize the importance of quickly adopting measures that first prioritize patient safety and data validity, then consider contingency measures such as telemedicine, virtual medical review, and remote monitoring. Successful adaptations of healthcare and patient management in response to COVID-19 have been fundamental to ensuring continuing clinical cancer research.

Abstract P4-10-17: Baseline and pharmacodynamic changes of circulating exosomal microRNAs predict early versus late progression to palbociclib plus endocrine therapy in patients with metastatic breast cancer. A sub-analysis of the PARSIFAL-1 trial

BACKGROUND: Palbociclib in combination with endocrine therapy (ET) is the first- or second-line standard of care for patients (pts) with hormone receptor (HR)-positive (+)/human epidermal growth factor receptor 2 (HER2)-negative (-) metastatic breast cancer (MBC). No clinically validated markers of long-term benefit from palbociclib have been established and the clinically relevant resistance mechanisms to cyclin-dependent kinases 4 and 6 inhibitors remain undefined. In the present study, we explored candidate circulating exosomal microRNAs (miRNAs) as putative predictors of benefit and/or resistance to palbociclib in combination with ET in pts included in the PARSIFAL-1 trial (ClinicalTrials.gov identifier: NCT02491983). MATERIALS AND METHODS: PARSIFAL-1 was a randomized, open-label, phase II trial aimed at evaluating the efficacy and safety of palbociclib plus either fulvestrant or letrozole in HR+/HER2- MBC pts. For the study of exosomal miRNAs, forty-five consenting pts were selected based on primary endocrine resistance according to the ABC-4 criteria. Nine pts who progressed within the first six months after treatment initiation in the absence of an objective response were considered Resistant and thirty-six pts who progressed more than six months after starting therapy were classified as Sensitive. Exosomes were isolated from plasma samples collected at study entry (baseline) and after 12 weeks of treatment initiation. Differences in miRNA expression between Resistant and Sensitive pts as well as miRNA pharmacodynamic changes between baseline and 12-week samples were assessed. Ribonucleic acid (RNA) was isolated using the miRNeasy plasma kit and the library preparation was done using the QIAseq miRNA library kit according to manufacturer’s instructions. All experiments were conducted at QIAGEN Genomic Services in Germany. Differential expression of miRNA between different conditions was studied using EdgeR statistical software package from Bioconductor. Estimated p-values for significantly differentially expressed miRNAs were adjusted using Benjamini-Hochberg’s False Discovery Rate (FDR). Differences in expression of miRNA with an FDR below 0.05 were considered significant. RESULTS: Sequencing of exosomal RNA and preparation of miRNA libraries were successful for all included samples, with good technical performance. On average, 2.8 million Unique Molecular Index-corrected reads were obtained for each sample and the average percentage of mappable reads was 34.5%. Overall, expression of miRNAs was higher in Resistant compared with Sensitive pts. Eight miRNAs were called as differentially expressed between the two groups. Four miRNAs (miR-1246; miR-375; miR-193a-5p; miR-181d-5p) were differentially expressed at baseline, three (miR-196a-5p, miR-200a-3p, miR-320d) were differentially expressed at 12 weeks, and expression of one miRNA (miR-141-3p) was consistently higher across both time points in Resistant pts. Significant pharmacodynamic changes in miRNA expression were observed both in Resistant and Sensitive pts. Seven miRNAs (miR-224-5p, miR-16-5p, let-7a-5p, miR-381-3p, miR-200c-3p, miR-493-3p, let-7b-5p) in Sensitive pts and three miRNAs (miR-223-3p, miR-126-3p, miR-320b) in Resistant pts were differentially expressed between baseline and 12-week samples. CONCLUSIONS: Circulating exosomal miRNA profiling is feasible in liquid biopsies from MBC pts. Differential expression of selected miRNAs at baseline or their pharmacodynamic modulation may predict benefit from palbociclib combined with ET in pts with HR+/HER2- MBC. Validation of the most promising miRNAs by custom quantitative PCR is warranted.

Citation Format: David Casadevall, Joan Albanell Mestres, Federico Rojo, Beatríz Bellosillo, Abel González, Violeta Serra, Meritxell Bellet, Miguel Angel Gil, Miquel Angel Pujana, Angelo Gámez, Enrique Espinosa, Peter Schmid, Joseph Gligorov, Frederik Marmé, Carlos L. Arteaga, Leonardo Mina, Andrea Malfettone, Miguel Sampayo, José Manuel Pérez-García, Javier Cortés, Antonio Llombart-Cussac. Baseline and pharmacodynamic changes of circulating exosomal microRNAs predict early versus late progression to palbociclib plus endocrine therapy in patients with metastatic breast cancer. A sub-analysis of the PARSIFAL-1 trial [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P4-10-17.

Abstract P6-18-12: EMBRACA: Efficacy and safety of talazoparib or physician's choice of therapy in patients with advanced breast cancer and a germline BRCA1/2 mutation: A regional analysis

Background: Talazoparib (TAL) prevents DNA damage repair by inhibiting poly (ADP-ribose) polymerase (PARP) enzymes and trapping PARP on DNA, resulting in cell death in BRCA1/2-mutated cells.

Methods: EMBRACA is an open-label, randomized, 2-arm phase 3 trial in which efficacy and safety of TAL (1 mg/d) were compared with physician's choice of therapy (PCT; capecitabine, eribulin, gemcitabine, vinorelbine) in patients (pts) with locally advanced or metastatic breast cancer (ABC) and a germline BRCA mutation (gBRCAm). Outcomes were assessed by region of the world (North America [NA]; Europe [EU]; rest of world [ROW]). Progression-free survival (PFS), objective response rate (ORR), and clinical benefit rate (CBR) at 24 wks were assessed; safety was also assessed.

Results: 431 pts were randomized 2:1. Pt characteristics were well balanced, although a higher percentage of pts in ROW had more severe disease (eg, triple-negative breast cancer [TNBC], Disease-free interval [DFI]&lt;12 mo, more distant metastases, more disease sites) and were on average younger than pts in NA/EU. TAL provided improvement in PFS, ORR, and CBR in all regions vs PCT. The most common toxicities with TAL included anemia, neutropenia, thrombocytopenia, fatigue, and nausea for all regions. Alopecia was less frequent with TAL in EU/ROW. Serious adverse events for pts receiving TAL were more frequent in EU than NA/ROW. Incidences of adverse events associated with permanent treatment discontinuation in pts receiving TAL were low in all regions and generally lower than for PCT.

Table 1CategoryNA* (N=156)EU* (N=190)ROW* (N=85)Mean age, years49.049.244.2Race, %   White76.971.152.9Black5.8-3.5Asian5.8-42.4Not reported-27.4-TNBC, %424447BRCA1**, %414748BRCA2**, %595352DFI&lt;12 mo, %313444Distant metastases, %949397≥3 disease sites, %474049PFS, (hazard ratio [HR]; [95% CI]); P value0.46 [0.29-0.74] P=.00090.52 [0.33-0.80]; P&lt;.0030.57 [0.31-1.07] ;P=.08ORR (odds ratio [OR] [95% CI]); P value5.54 [2.4-16.1];P&lt;.00013.75 [1.57-9.87]; P=.0016.7 [1.61-28.39]; P=.001CBR (OR [95% CI]); P value4.71 [2.20-10.57]; P&lt;.00013.39 [1.56-7.36]; P=.00075.70 [1.70-17.13]; P=.002Hematologic AEs, %   Anemia50.558.642.6Neutropenia31.332.346.3Thrombocytopenia28.322.635.2Nonhematologic AEs, %   Fatigue59.643.650.0Nausea47.545.957.4Headache32.330.837.0Alopecia34.320.320.4Serious adverse events, %25.340.622.2Treatment discontinuation, n/N, (%)   TAL7/99 (7.1)12/133 (9.0)3/54 (5.6)PCT7/43 (16.3)3/54 (5.6)2/29 (6.9)AE, adverse event; CI, confidence interval; *NA (United States); EU (Belgium, France, Germany, Ireland, Italy, Poland, Spain, United Kingdom, Russia, Ukraine, Israel); ROW (Brazil, Korea, Australia, Taiwan).**Central laboratory.

Conclusions: In pts with gBRCAm ABC, TAL demonstrated significant improvements in clinical outcomes compared with PCT regardless of the region of the world in which they lived. However, slight differences among the regions in baseline characteristics were noted, possibly due to regional variation in diagnosis and detection of gBRCAm ABC as well as different treatment paradigms for metastatic breast cancer.

Funding: Medivation LLC, acquired by Pfizer.

Citation Format: Mina L, Lee K-H, Gonçalves A, Woodward N, Hurvitz SA, Diab S, Yerushalmi R, Goodwin A, Moreira Costa Zorzetto M, Kim S-B, Czibere A, Tudor IC, Gauthier E, Litton JK, Ettl J. EMBRACA: Efficacy and safety of talazoparib or physician's choice of therapy in patients with advanced breast cancer and a germline BRCA1/2 mutation: A regional analysis [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-18-12.

MRS Shimming: An Important Point Which Should not be Ignored

BACKGROUND

Proton magnetic resonance spectroscopy (MRS) is a well-known device for analyzing the biological fluids metabolically. Obtaining accurate and reliable information via MRS needs a homogeneous magnetic field in order to provide well-defined peaks and uniform water suppression. There are lots of reasons which can disturb the magnetic field homogeneity which can be corrected by a process known as shimming. This study is intended to recall the importance of shimming and also the significant role of quality control (QC) in achieving an accurate quantification.

MATERIAL AND METHOD

An acrylic cylindrical quality control phantom was designed as an analog of brain MRS test phantoms in order to control the accuracy of the obtained signal of a 1.5 T Siemens MRI system which belonged to one of Shiraz hospitals. The signal of NAA, Cho, Cr, the combination of these metabolites and also the distilled water, which was used in this study, was evaluated using separate phantoms. A QC test was performed using Siemens QC phantom and a standard test phantom.

RESULTS

The spectrum of our home- made phantom had a significant difference with the expected spectrum. The results of checking the spectrum of metabolites separately also confirmed that there was a systemic problem that affects all the signals originated from all metabolites and even the pure distilled water. The MRS system could not pass QC tests, and peak broadening was common in all spectra. The complex spectrum of standard test phantom was not produced successfully by the MRS system.

DISCUSSION

By a simple check of the water peak characteristics, lots of information can be obtained, one of which is the status of shimming that has a considerable effect on the accuracy of the spectrum. Thus, performing an automatic or manual shimming is not a criterion of the spectrum accuracy, and performing a periodic quality control using a test phantom by a specialist is necessary.

CONCLUSION

Briefly, the quality control of MRS and all the other clinical device must be taken seriously. Sometimes QC can be the boundary of a right or a wrong decision for the patient.

Factors underlying metastatic breast cancer patients' perceptions of symptom importance: a qualitative analysis

The symptom literature in cancer has primarily examined symptom severity, frequency and distress. Assessing cancer patients' perceptions of symptom importance-how important it is for them to see improvement in a symptom following an intervention-and factors influencing these judgments would also inform patient-centred care, but this analysis has not been undertaken. This qualitative study aimed to identify factors underlying perceptions of symptom importance among 25 symptomatic metastatic breast cancer (MBC) patients. Participants were recruited from a cancer centre in the Midwestern USA. Semi-structured interviews focused on patients' rationale for considering common symptoms (i.e., anxiety, sadness, sleep problems, pain or fatigue) to be important. Thematic analyses revealed five interrelated factors underlying MBC patients' perceptions of symptom importance: activity restriction, concentration difficulties, exacerbation of other physical symptoms, symptom-related long-term health concerns and negative impact on their relationships with others. Patients most frequently stated that a physical or psychological symptom was important because of the resulting activity restriction. Additionally, some patients considered pain to be important because it signalled potential long-term health concerns, such as worsening metastatic disease. Findings suggest that clinicians should take into account MBC patients' perceptions of symptom importance and factors underlying these judgments when making shared treatment decisions.

Weight reduction in a normal population

Weight loss of more than 2 kg under the guidance of a trained nurse was achieved over a 12-month period in 38% of overweight hospital and transport workers. Males over 50 were the subgroup most successful in losing weight. Weight loss achieved by older males with an "off-hand" as compared with an "energetic" approach was similar up until nine months, after which the "energetic" approach was more effective. Females on an "energetic" diet were successful up until nine months only. The "off-hand" approach is acceptable to more people and is less time-consuming. It should therefore be seriously considered by a public health authority which seeks to promote weight reduction in the general community.