ASTEFANIA: adjuvant ado-trastuzumab emtansine and atezolizumab for high-risk, HER2-positive breast cancer.

There is a strong rationale for combining HER2-targeted therapies with cancer immunotherapy to increase efficacy in breast cancer, particularly in the early-stage setting, where the immune system has not been weakened by heavy pretreatment. ASTEFANIA aims to evaluate the efficacy of adjuvant atezolizumab in combination with ado-trastuzumab emtansine in patients with high-risk, HER2-positive early breast cancer and residual disease following HER2-based neoadjuvant therapy. Eligible patients will be randomized to receive ado-trastuzumab emtansine in combination with either atezolizumab or placebo for 14 cycles within 12 weeks of primary surgery. The primary outcome is invasive disease-free survival and secondary outcomes include additional efficacy end points, safety and pharmacokinetics. The study plans to enroll 1700 patients across 32 counties. Clinical Trial Registration: NCT04873362 (ClinicalTrials.gov).

Subcutaneous trastuzumab with pertuzumab and docetaxel in HER2-positive metastatic breast cancer: Final analysis of MetaPHER, a phase IIIb single-arm safety study.

PURPOSE: Intravenous trastuzumab, pertuzumab, and docetaxel are first-line standard of care for patients with HER2-positive metastatic breast cancer (mBC). MetaPHER is the first study assessing the safety and tolerability of subcutaneous trastuzumab plus intravenous pertuzumab and chemotherapy in a global patient population with HER2-positive mBC. METHODS: In this open-label, single-arm, multicenter, phase 3b study, eligible patients were ≥ 18 years old with histologically/cytologically confirmed previously untreated HER2-positive mBC. All received ≥ 1 subcutaneous trastuzumab 600 mg fixed dose plus intravenous pertuzumab (loading dose: 840 mg/kg; maintenance: 420 mg/kg) and docetaxel (≥ 6 cycles; initial dose 75 mg/m2) every 3 weeks. The primary objective was safety and tolerability; secondary objectives included efficacy. RESULTS: At clinical cutoff, 276 patients had completed the study; median duration of follow-up was 27 months. The most common any-grade adverse events were diarrhea, alopecia, and asthenia; the most common grade ≥ 3 events were neutropenia, febrile neutropenia, and hypertension. There were no cardiac deaths and mean left ventricular ejection fraction was stable over time. Median investigator-assessed progression-free survival was 18.7 months; objective response rate was 75.6%. CONCLUSIONS: Safety and efficacy with subcutaneous trastuzumab plus intravenous pertuzumab and docetaxel in mBC are consistent with historical evidence of intravenous trastuzumab with this combination. Findings further support subcutaneous administration not affecting safety/efficacy profiles of trastuzumab in HER2-positive BC with increased flexibility in patient care. A fixed-dose combination of pertuzumab and trastuzumab for subcutaneous injection has recently been approved for the treatment of HER2-positive early/mBC, further addressing the increasing relevance of and need for patient-centric treatment strategies. TRIAL REGISTRATION: NCT02402712.

Adjuvant Pertuzumab and Trastuzumab in Early HER2-Positive Breast Cancer in the APHINITY Trial: 6 Years' Follow-Up.

PURPOSE: APHINITY, at 45 months median follow-up, showed that pertuzumab added to adjuvant trastuzumab and chemotherapy significantly improved invasive disease-free survival (IDFS) (hazard ratio 0.81 [95% CI, 0.66 to 1.00], P = .045) for patients with early human epidermal growth factor receptor 2 (HER2)-positive breast cancer (BC), specifically those with node-positive or hormone receptor (HR)-negative disease. We now report the preplanned second interim overall survival (OS) and descriptive updated IDFS analysis with 74 months median follow-up. METHODS: After surgery and central HER2-positive confirmation, 4,805 patients with node-positive or high-risk node-negative BC were randomly assigned (1:1) to either 1-year pertuzumab or placebo added to standard adjuvant chemotherapy and 1-year trastuzumab. RESULTS: This interim OS analysis comparing pertuzumab versus placebo did not reach the P = .0012 level required for statistical significance (P = .17, hazard ratio 0.85). Six-year OS were 95% versus 94% with 125 deaths (5.2%) versus 147 (6.1%), respectively. IDFS analysis based on 508 events (intent-to-treat population) showed a hazard ratio of 0.76 (95% CI, 0.64 to 0.91) and 6-year IDFS of 91% and 88% for pertuzumab and placebo groups, respectively. The node-positive cohort continues to derive clear IDFS benefit from pertuzumab (hazard ratio 0.72 [95% CI, 0.59 to 0.87]), 6-year IDFS being 88% and 83%, respectively. Benefit was not seen in the node-negative cohort. In a subset analysis, IDFS benefit from pertuzumab showed a hazard ratio of 0.73 (95% CI, 0.59 to 0.92) for HR-positive disease and a hazard ratio of 0.83 (95% CI, 0.63 to 1.10) for HR-negative disease. Primary cardiac events remain < 1% in both the treatment groups. No new safety signals were seen. CONCLUSION: This analysis confirms the IDFS benefit from adding pertuzumab to standard adjuvant therapy for patients with node-positive HER2-positive early BC. Longer follow-up is needed to fully assess OS benefit.

Pertuzumab, trastuzumab, and docetaxel for HER2-positive metastatic breast cancer (CLEOPATRA): end-of-study results from a double-blind, randomised, placebo-controlled, phase 3 study.

BACKGROUND: CLEOPATRA was a phase 3 study comparing the efficacy and safety of pertuzumab, trastuzumab, and docetaxel with placebo, trastuzumab, and docetaxel in patients with HER2-positive metastatic breast cancer. In the primary analysis and subsequent reports, progression-free and overall survival were significantly improved in the pertuzumab group compared with the placebo group. Here, we report the end-of-study analysis of CLEOPATRA. METHODS: This was a double-blind, randomised, placebo-controlled, phase 3 trial that was done at 204 centres in 25 countries. Eligible patients were 18 years or older, had HER2-positive, metastatic breast cancer, had not received previous chemotherapy or biological treatment for their metastatic disease, and had an Eastern Cooperative Oncology Group performance status of 0 or 1. All study drugs were given intravenously, every 3 weeks. Patients were assigned to receive either pertuzumab or placebo at a loading dose of 840 mg, and 420 mg thereafter; plus trastuzumab at 8 mg/kg loading dose and 6 mg/kg thereafter; and docetaxel at 75 mg/m2, escalating to 100 mg/m2 if tolerated. Pertuzumab or placebo and trastuzumab were given until disease progression; docetaxel was given for six cycles, or longer at the investigators' discretion. Randomisation (1:1) was done by use of an interactive voice-response system and was stratified by geographical region (Asia, Europe, North America, or South America) and previous treatment (previous adjuvant or neoadjuvant chemotherapy vs none). The primary endpoint was independent review facility-assessed progression-free survival, which has been reported previously. Since the confirmatory overall survival analysis had also occurred before this prespecified end-of-study analysis, analyses presented here are descriptive. Overall survival analyses were based on the intention-to-treat population with crossover patients analysed in the placebo group; analyses were not adjusted for crossover to the pertuzumab group and are likely to be conservative. Safety analyses were based on treatment received; crossover patients were counted in the placebo group up to the day before first pertuzumab dose. This trial is registered with ClinicalTrials.gov, number NCT00567190. FINDINGS: Between Feb 12, 2008, and July 7, 2010, 1196 patients were assessed for eligibility, of whom 808 were enrolled and randomly assigned. 402 patients were assigned to receive docetaxel plus trastuzumab plus pertuzumab, and 406 patients were assigned to receive docetaxel plus trastuzumab plus placebo. Clinical cutoff for this analysis was Nov 23, 2018. Between July 2012 and clinical cutoff, 50 patients crossed from the placebo to the pertuzumab group. Median follow-up was 99·9 months in the pertuzumab group (IQR 92·9-106·4) and 98·7 months (90·9-105·7) in the placebo group. Median overall survival was 57·1 months (95% CI 50-72) in the pertuzumab group and 40·8 months (36-48) in the placebo group (hazard ratio 0·69, 95% CI 0·58-0·82); 8-year landmark overall survival rates were 37% (95% CI 31-42) in the pertuzumab group and 23% (19-28) in the placebo group. The most common grade 3-4 adverse event was neutropenia (200 [49%] of 408 patients in the pertuzumab group, 183 [46%] of 396 patients in the placebo group). Five (1%) of 408 patients in the pertuzumab group and six (2%) of 396 patients in the placebo group had treatment-related deaths. One new serious adverse event suggestive of congestive heart failure (pertuzumab group) and one new symptomatic left ventricular systolic dysfunction (post-crossover) occurred since the previous analysis. INTERPRETATION: Our analysis shows that the previously observed improvements in overall survival with pertuzumab, trastuzumab, and docetaxel versus placebo, trastuzumab, and docetaxel were maintained after a median of more than 8 years of follow-up. The long-term safety and cardiac safety profiles of pertuzumab, trastuzumab, and docetaxel were maintained in the overall safety population and within crossover patients. HER2-targeted therapy has changed the natural history of HER2-positive metastatic breast cancer, with the dual blockade of pertuzumab and trastuzumab, with docetaxel, demonstrating an 8-year landmark overall survival rate of 37%. FUNDING: F Hoffmann-La Roche and Genentech.

Topoisomerase 2 is dispensable for the replication and segregation of small yeast artificial chromosomes (YACs).

DNA topoisomerases are thought to play a critical role in transcription, replication and recombination as well as in the condensation and segregation of sister duplexes during cell division. Here, we used high-resolution two-dimensional agarose gel electrophoresis to study the replication intermediates and final products of small circular and linear minichromosomes of Saccharomyces cerevisiae in the presence and absence of DNA topoisomerase 2. The results obtained confirmed that whereas for circular minichromosomes, catenated sister duplexes accumulated in the absence of topoisomerase 2, linear YACs were able to replicate and segregate regardless of this topoisomerase. The patterns of replication intermediates for circular and linear YACs displayed significant differences suggesting that DNA supercoiling might play a key role in the modulation of replication fork progression. Altogether, this data supports the notion that for linear chromosomes the torsional tension generated by transcription and replication dissipates freely throughout the telomeres.

DNA methylation-mediated silencing of PU.1 in leukemia cells resistant to cell differentiation.

In mice, the proviral integration of the Friend Spleen Focus Forming Virus (SFFV) within the PU.1 locus of erythroid precursors results in the development of erythroleukemia. SFFV integrates several kilobases upstream of the PU.1 transcription initiation start site leading to the constitutive activation of the gene which in turn results in a block of erythroid differentiation. In this study we have mapped and sequenced the exact location of the retroviral integration site. We have shown that SFFV integrates downstream of a previously described upstream regulatory element (URE), precisely 2,976 bp downstream of the URE-distal element. We have also found that SFFV persists integrated within the same location in resistant cell lines that have lost their differentiation capacity and in which case PU.1 remains silent. We have examined the methylation status of PU.1 and found that in resistant cells the nearby CpG islands remained methylated in contrast to a non-methylated status of the parental cell lines. Treatment with 5-aza-2'-deoxycytidine caused resistant cells to differentiate yet only when combined with HMBA. Altogether these results strongly suggest that methylation plays a crucial role with regard to PU.1 silencing. However, although demethylation is required, it is not sufficient to overcome the differentiation impasse. We have also showed that activation blockage of the Epo/Epo-R pathway remains despite of the absence of PU.1.