Abstract OT2-07-02: Trastuzumab deruxtecan (DS-8201a) vs investigator's choice of treatment in subjects with HER2-positive, unresectable and/or metastatic breast cancer who previously received T-DM1: A randomized, phase 3 study

Background: There is no uniform standard of care for HER2-positive breast cancer (BC) after disease progression on ado-trastuzumab emtansine (T-DM1). DS-8201a is a novel HER2-targeted antibody-drug conjugate (ADC) with a humanized HER2 antibody attached to a topoisomerase I inhibitor payload by a cleavable peptide-based linker, and with a drug-to-antibody ratio of 7 to 8. It is designed with the goal of improving critical attributes of an ADC. In an ongoing phase 1 trial, DS-8201a showed promising antitumor activity in HER2-positive BC previously treated with T-DM1 (confirmed objective response rate [ORR] of 54.5%; April 2018 data cutoff; Iwata et al, ASCO 2018). Based on preliminary results from the phase 1 trial, DS-8201a received FDA breakthrough therapy and fast track designations for metastatic BC that progressed after prior treatment with T-DM1. The pivotal, phase 2 DESTINY-BREAST01 trial in this population with HER2-positive BC who received prior T-DM1 is ongoing (Baselga et al, ASCO 2018).

Study Description: This multicenter, open-label, phase 3 trial will assess the efficacy and safety of DS-8201a in subjects with HER2-positive (IHC 3+ or IHC 2+/ISH+; confirmed by centralized testing) unresectable and/or metastatic BC whose disease progressed on or after T-DM1 (NCT03523585, DESTINY-BREAST02). Approximately 600 subjects will be randomized (2:1) to DS-8201a or investigator's choice of treatment (trastuzumab plus capecitabine or lapatinib plus capecitabine). Randomization is stratified by hormone receptor status, prior pertuzumab treatment, and history of visceral disease. DS-8201a (5.4 mg/kg) will be administered IV once every 3 weeks. Progression free survival (PFS) based on blinded, independent central review using RECIST v1.1 criteria is primary efficacy endpoint; overall survival (OS) is the key secondary endpoint. Other secondary efficacy endpoints are ORR, duration of response, clinical benefit rate, and PFS based on investigator assessment. Safety assessments include serious and treatment-emergent adverse events, physical examinations, vital signs, and clinical laboratory parameters. Health-related quality of life will also be measured. The primary analysis for PFS will occur when approximately 372 PFS events have been observed; providing 90% power to detect a hazard ratio of 0.70 in PFS (a 43% improvement in median PFS from 3.3 months with investigator's choice to 4.7 months with DS-8201a) with a 1-sided alpha of 0.025. An interim OS analysis is planned at the time of the PFS analysis. Final OS analysis will occur when approximately 428 OS events have been observed. Long-term follow-up will continue after the primary analysis every 3 months until death, withdrawal of consent, loss to follow-up, or study closure. Efficacy analyses will include all randomized subjects, and safety analyses will include all randomized subjects who received ≥1 dose of study treatment. The study will enroll subjects from approximately 160 sites including in North and South America, Europe, and Asia. For further information on this trial, contact Fabrice André at FABRICE.ANDRE@gustaveroussy.fr or visit clinicaltrials.gov.

Citation Format: André F, Shahidi J, Lee C, Wang K, Krop IE. Trastuzumab deruxtecan (DS-8201a) vs investigator's choice of treatment in subjects with HER2-positive, unresectable and/or metastatic breast cancer who previously received T-DM1: A randomized, phase 3 study [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 OT2-07-02.

Abstract P6-17-06: Characterization, monitoring and management of interstitial lung disease in patients with metastatic breast cancer: Analysis of data available from multiple studies of DS-8201a, a HER2-targeted antibody drug conjugate with a topoisomerase I inhibitor payload

Background: Several classes of anti-cancer agents including certain immunotherapies, systemic chemotherapies, and targeted therapies including trastuzumab and T-DM1 increase the risk of interstitial lung disease (ILD) and fatal cases have been reported. For DS-8201a, interim efficacy and safety analyses of available data established a final recommended dose of 5.4 mg/kg IV q3wk in advanced HER2-positive breast cancer (BC). Based on preliminary clinical results, ILD was identified as an important risk for DS-8201a. A robust monitoring and management plan was established across all studies and an international, independent ILD adjudication committee (AC) reviews the cases reported as ILD on an ongoing basis.

Methods: All subjects (sbj) who received ≥1 dose of DS-8201a across 7 ongoing studies were included in this analysis. Reported ILD (standardized MedDRA Query terms) included the terms ILD, pneumonitis, and organizing pneumonia. ILD frequencies were calculated based on investigator's assessment and after adjudication. The analysis of potential risk factors associated with ILD is ongoing.

Results: As of 21 June 2018, 448 sbj received ≥1 dose of DS-8201a across multiple tumor types, including BC. Of the 321 sbj with BC, 173 (53.9%) were from Japan, 103 (32.1%) from the US, and 45 (14.0%) from 6 other countries (Spain, South Korea, Taiwan, Belgium, France, and Italy). These sbj received 1 of 7 doses of DS-8201a (0.8 mg/kg: 3 sbjs, 1.6 mg/kg: 1 sbj, 3.2 mg/kg: 3 sbjs, 5.4 mg/kg: 111 sbjs, 6.4 mg/kg: 178 sbj, 7.4 mg/kg: 20 sbj, 8.0 mg/kg: 5 sbj). Overall, 44 cases of potential ILD were reported by the investigators across all tumor types (44/448, 9.8%; Grade ≥3 10/448, 2.2%). In sbj with BC who received 5.4 mg/kg, any grade and Grade ≥3 investigator-reported ILD were 7.2% (8/111) and 0.9% (1/111), respectively. The ILD AC assessed 30 of 44 cases; 22 were considered drug-related ILD, 4 were ILD but not drug-related, and 4 were found not to be ILD. For adjudicated drug-related ILD cases, the median time to onset was 159 (range; 46-591) days from the time of first dose.

  Grade 1 Grade 2 Grade 3 Grade 4 Grade 5 All Grades All tumors, All doses (N=448)      Investigator-reported20 (4.5)14 (3.1)4 (0.9)1 (0.2)5 (1.1)44 (9.8)Cases adjudicated13840530Adjudicated as drug-related ILD9 (2.0)6 (1.3)3 (0.7)04 (0.9)22 (4.9) BC, All doses (N=321)      Investigator-reported17 (5.3)11 (3.4)3 (0.9)1 (0.3)4 (1.2)36 (11.2)Cases adjudicated11830426Adjudicated as drug-related ILD8 (2.5)6 (1.9)3 (0.9)04 (1.2)21 (6.5) BC, 5.4 mg/kg (N=111)      Investigator-reported4 (3.6)3 (2.7)001 (0.9)8 (7.2)Cases adjudicated120014Adjudicated as drug-related ILD00001 (0.9)1 (0.9)n (%), except where noted

Conclusions: These analyses confirm that ILD is an important identified risk for DS-8201a. Further analyses are ongoing to better understand the potential risk factors associated with the incidence of on-treatment ILD. When ILD is suspected, early diagnosis through appropriate imaging, laboratory tests, and pulmonary consultation as well as prompt management with steroids are recommended.

Citation Format: Powell CA, Camidge DR, Gemma A, Kusumoto M, Baba T, Kuwano K, Bankier A, Kiura K, Tamura K, Modi S, Tsurutani J, Doi T, Iwata H, Krop IE, Zhang L, Jasmeet S, Saito K, Shahidi J, Yver A, Takahashi S. Characterization, monitoring and management of interstitial lung disease in patients with metastatic breast cancer: Analysis of data available from multiple studies of DS-8201a, a HER2-targeted antibody drug conjugate with a topoisomerase I inhibitor payload [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 P6-17-06.

Correlation of EGFR-expression with safety and efficacy outcomes in SQUIRE: a randomized, multicenter, open-label, phase III study of gemcitabine-cisplatin plus necitumumab versus gemcitabine-cisplatin alone in the first-line treatment of patients with stage IV squamous non-small-cell lung cancer

SQUIRE was a phase III study of gemcitabine and cisplatin with or without necitumumab in patients with metastatic squamous NSCLC. The majority of SQUIRE patients had EGFR protein expressing tumors. Similar to SQUIRE ITT, patients with EGFR protein expressing tumors benefitted from addition of necitumumab to chemotherapy with a safety profile consistent with that of the overall SQUIRE population.

Background

SQUIRE demonstrated addition of necitumumab to gemcitabine and cisplatin significantly improved survival in patients with stage IV sq-NSCLC. Here, we report additional outcomes for the subpopulation of patients with tumor epidermal growth factor receptor (EGFR) protein expression.

Patients and methods

Patients with pathologically confirmed stage IV sq-NSCLC were randomized 1:1 to receive a maximum of six 3-week cycles of gemcitabine (1250 mg/m² i.v., days 1 and 8) and cisplatin (75 mg/m² i.v., day 1) chemotherapy with or without necitumumab (800 mg i.v., days 1 and 8). Patients in the chemotherapy plus necitumumab group with no progression continued on necitumumab alone until disease progression or intolerable toxicity. SQUIRE included mandatory tissue collection. EGFR protein expression was detected by immunohistochemistry (IHC) in a central laboratory. Exploratory analyses were pre-specified for patients with EGFR protein expressing (EGFR > 0) and non-expressing (EGFR = 0) tumors.

Results

A total of 982 patients [90% of intention-to-treat (ITT)] had evaluable IHC results. The large majority of these patients (95%) had tumor samples expressing EGFR protein; only 5% had tumors without detectable EGFR protein. Overall survival (OS) for EGFR > 0 patients was significantly longer in the necitumumab plus gemcitabine–cisplatin group than in the gemcitabine–cisplatin group {stratified hazard ratio (HR) 0.79 [95% confidence interval (CI) 0.69, 0.92; P = 0.002]; median 11.7 months (95% CI 10.7, 12.9) versus 10.0 months (8.9, 11.4)}. Additionally, an OS benefit was seen in all pre-specified subgroups in EGFR > 0 patients. However, OS HR for EGFR = 0 was 1.52. Adverse events of interest with the largest difference between treatment groups in EGFR > 0 patients (Grade ≥3) were hypomagnesemia (10% versus <1%) and skin rash (6% versus <1%).

Conclusions

In line with SQUIRE ITT, addition of necitumumab to gemcitabine–cisplatin significantly prolonged OS and was generally well tolerated in the subpopulation of patients with EGFR-expressing advanced sq-NSCLC. The benefit from addition of necitumumab to chemotherapy was not apparent in this analysis for the small subgroup of patients with non-EGFR-expressing tumors.

Clinical Trial

NCT00981058.

Not telling the truth: circumstances leading to concealment of diagnosis and prognosis from cancer patients

While autonomy has gradually become a key concept in the doctor-patient relationship, truth-telling is far from being the norm in many countries in the world. Despite the general agreement on the benefits of open communication between physicians and cancer patients, there is still strong resistance against disclosure of cancer diagnosis and prognosis in many cultures. Although fear of causing psychological morbidity to patients and their reluctance to find out the truth are two main justifications of non-disclosure attitudes, there are other important contributing factors that need to be further explored and better understood including those related to the relatives, doctors and healthcare systems. Cultural disparities in attitudes towards truth-telling persist; however, these differences should not be used as excuses not to respect the rights and individual preferences of cancer patients by making assumptions based on their age, sex, type of cancer, language and/or cultural background.

Treatment and prognosis of epithelial ovarian cancer in Iran

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Background: Ovarian cancer is the most lethal gynecologic malignancy in the US, with 14,500 women dying of this disease annually. The aims of this study are to describe brief epidemiologic variations, response rate for usual chemotherapy regimen and progression free survival analysis in Iranian patients. Patients and Methods: 98 women with confirmed ovarian cancer who have been undergone surgery followed by chemotherapy at three hospitals in Tehran (Iran) between 1997 and 2003 were enrolled in this retrospective study. FIGO staging system has been applied. We have collected data regarding age, pathologic variations, surgical procedure (complete, partial, biopsy), chemotherapy, response rate, and time to progression of disease. Results: From a total of 98 patients, there were 80 (81.6%) epithelial, 12 (12.2%) germ cell, 5 (5.1%) granulosa cell tumors and one case of lymphoma. Response rate have been evaluated for 60 patients with epithelial cancer. Overall mean age was 46.7 and average age for epithelial tumors and non-epithelial tumors were 49.6 and 34.3 respectively. Complete surgical procedure with staging and optimal residue had been performed for 18 patients. Stage III was the most common stage (46.1%). In 78.3% of patients complete or partial response were seen, while 21.7% of patients showed stable or progressive disease. The most important prognostic factors were stage, and extent of surgical procedure. Median progression-free survival was 24.2 months. Conclusion: Overall average-age of our patients is lower than expected. Besides, a large proportion of the patients are referred in advanced stages. Although, higher response rate has been produced by taxane-based regimen in comparison of traditional chemotherapy; but it was not statistically significant. Retrospective evaluation, low number of the patients, non-uniform usage of chemotherapy regimen could influence our results.

No significant financial relationships to disclose.

Heterogeneity in disease-free survival in breast cancer patients

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Background: Breast cancer is the most common cancer and women’s health problems in Iran. There are some known prognostic factors for occurrence of metastasis after surgery. However, there are some other unknown factors affect the risk of metastasis. The purpose of this study was to determine the value of known prognostic factors by accounting for patient-specific effect, the rate metastasis in breast cancer patients who received surgical treatment followed by adjuvant treatment in Iran. Methods: Among 174 women whom have been undergone surgery followed by adjuvant therapy at three hospitals in Tehran, Iran during 3 years 117 have met the including criteria. Women with defined breast cancer with no distant metastases in time of diagnosis whom have been undergone MRM or BCS were enrolled. Tumors were classified according to the TNM system of the American Joint Committee on cancer (AJCC). Grading was performed according to Scarff-Bloom-Richardson method. ER and C-erb2 was measured by immunohistochemistry (IHC) method. The patients have been followed regularly by routine clinical, lab profile, serologic markers (CEA,CA15–3) and Para clinical examinations. Results: The median relapse- free survival for patients in study was 49.6 month. The median time to experience second metastasis was 22.5 month. 44 (38% ) patients developed metastasis. 20 (45%) of those experienced second metastasis. the Frailty model showed that age, size of tumor, number of positive lymph nodes and histologic grade had a significant effect on the risk of metastasis (p<.05) and there was a heterogeneity between patients after adjusting for covariates. Conclusion: Many patients who referred to cancer centers were not detected at early stage and they will meet more risk for relapse. The known risk factors describe the risk of metastasis partly and other unknown or unmeasured factors, such as environmental or genetics, are important to describe the risk of metastasis in breast cancer. Family history has no significant effect on event- free survival.

No significant financial relationships to disclose.