Abstract OT2-15-01: COntinue the SaMe systemic therapy after local ablative therapy for Oligoprogression in metastatic breast cancer - the COSMO study

Background

Patients with metastatic breast cancer (MBC) are usually treated with palliative systemic therapy until progression or unacceptable toxicity. When progression occurs, clinicians typically switch to the next line of systemic therapy. However, this strategy might be suboptimal in case of mixed response or oligoprogression. Oligoprogression refers to a situation in which inter-lesion heterogeneity causes one or few metastatic lesions to progress while the vast majority of the metastatic burden responds to the treatment. Locally ablative treatment of the progressive lesion(s) with radiotherapy, resection or radiofrequency ablation may enable continuation of otherwise effective systemic treatment. Solid data to support this approach, however, is lacking at this moment.

Study design

The COSMO study is an investigator-initiated single-arm phase 2 study. It is intended to be a multicenter study.

Eligibility criteria

Patients with MBC and oligoprogression, defined as 1-2 progressive lesions while the majority of the metastatic burden remains stable or in remission, are eligible. Current systemic therapy must be 1st or 2nd line and patients must have responded to this systemic therapy for at least six months prior to the occurence of oligoprogression. The aberrant lesion must be amenable to locally ablative therapy. All eligibility criteria may be found in table 1: eligibility criteria. Aim To investigate efficacy of local ablation of aberrant lesions combined with continuation of the same systemic therapy in patients with oligoprogression of MBC.

Primary endpoint:

Progression-free survival rate at six months (PFS-6).

Secondary endpoints:

- PFS

- Overall survival

- Time to next line of systemic therapy

Primary and secondary endpoints will also be stratified by localization of progressive lesion and BC subtype (ER+/HER2- vs. HER2+ vs. TN).

- Local control rate of lesion treated with LAT at 12 months

- Complications due to LAT

- Quality of life

- Incidence of visceral crisis

Exploratory endpoints:

- Biomarkers, including receptor (ER/PR/HER2), PD-L1 and gene expression patterns in biopsies from progressive and responding lesions

- Prognostic value of ctDNA at oligoprogression and during the course of treatment

Statistical methods

An A’hern design was chosen to conduct this study. As null-hypothesis (H0), PFS-6 rate ≤ 25% is set. The alternative hypothesis (H1) is PFS-6-rate ≥ 40%. Hypotheses were set to meet criteria for clinical significance, as stated by experts in the field. Setting one-sided α = 0.05 and a desirable power=95%, 107 evaluable patients are needed. To account for 10% of the patients to be unevaluable, 118 included patients are needed. An early stopping rule for safety is applicable: if out of the first 45 patients ≥4 of these patients have developed visceral crisis, the study will be closed early.

Accrual

Start: July 2022

Target: 118 patients

Estimated accrual time: 2-3 years

Further information

Corresponding author: c.almekinders@nki.nl

Clinicaltrials.gov identifier: NCT05301881

This study is funded by the Maarten van der Weijden foundation.

This study was developed during the 21st EORTC/ESMO/AACR workshop on methods in clinical cancer research (MCCR).

Table 1. Eligibility criteria.

Citation Format: Cornelia AM Almekinders, Tessa G Steenbruggen, Ingrid A. Mandjes, Marta Lopez-Yurda, Monique EMM Bos, Terry G Wiersma, Gabe S. Sonke. COntinue the SaMe systemic therapy after local ablative therapy for Oligoprogression in metastatic breast cancer - the COSMO study [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr OT2-15-01.

Abstract OT2-01-08: SEQUence of Endocrine therapy in advanced Luminal Breast cancer (SEQUEL-Breast): A phase 2 study on fulvestrant beyond progression in combination with alpelisib for PIK3CA-mutated, HR+ HER2- advanced breast cancer

Goal To investigate the efficacy of alpelisib added to fulvestrant beyond progression in patients with HR+ HER2- advanced breast cancer (ABC). Background The SOLAR-1 study (Andre et al, 2019) has shown that the addition of alpelisib, an alpha-specific PI3K-inhibitor to fulvestrant led to a PFS-benefit of 5.3 months in patients with PIK3CA-mutated HR+ HER2- ABC. In this study, patients were fulvestrant-naive, and only 6% of this population was previously treated with a CDK4/6 inhibitor (CDK4/6i). Nowadays, most patients have been treated with a CDK4/6i, either combined with an aromatase-inhibitor (AI) in 1st line, or with fulvestrant in the 1st or 2nd line setting. Results of the ongoing Dutch SONIA-trial (NCT03425838) will show whether the addition of CDK4/6i to an AI in 1st line is superior to the addition of CDK4/6i to fulvestrant in 2nd line. Patients who have progressed on a CDK4/6i in either line and fulvestrant may be treated with fulvestrant and alpelisib. However, the efficacy of fulvestrant beyond progression combined with alpelisib is unknown. Aim of this study The aim is to determine if treatment with fulvestrant beyond progression and alpelisib results in a clinically meaningful median PFS of ≥6 months. Primary endpoint: Progression-free survival (PFS). Secondary endpoints: ‘On treatment’ PFS Overall survival Objective Response Rate Clinical Benefit Rate Duration of response Safety Risk factors for alpelisib-induced hyperglycemia Quality of life Pharmacokinetics Prognostic value of ctDNA Mechanisms of resistance Trial design The SEQUEL-Breast trial is a nationwide Dutch investigator-initiated phase 2 trial. 25 centers are expected to participate in the SEQUEL-Breast. Clinicaltrials.gov identifier: NCT05392608 Intervention: fulvestrant beyond progression combined with alpelisib. Population Patients must be adults with HR+ HER2- ABC with an activating PIK3CA-mutation. Prior treatment with an AI and fulvestrant is mandatory, as well as prior treatment with a CDK4/6i in either line. Patients must have progressed on fulvestrant (+/- CDK4/6i), and fulvestrant must be the most recent line of therapy. Patients with ECOG performance score 0,1 or 2 are eligible, as well as those with controlled (HbA1C < 8.4%) diabetes mellitus type 2. Patients with uncontrolled diabetes, visceral crisis, symptomatic CNS metastases or clinically relevant heart disease are ineligible. Patients with diseases or previous surgery that might affect the bioavailability of alpelisib, those in need to use CYP3A4 inhibitors or BRCP inhibitors, as well as patients with any other conditions that would put them at particular risk when partaking in the study, are also ineligible. Accrual Start: June 2022 Accrual, June 27: 3 patients Target: 105 patients (minimum) to 130 patients (maximum) Estimated accrual time: 2-3 years Statistical considerations For sample size calculation, H1 (median PFS≥6 months) is weighed against H0 (median PFS≤4 months) in a one sample log rank test. α=0.05 β=0.1. 71 events are needed. We estimated that inclusion of 79 patients is required to reach 71 events, given an accrual time of 36 months and a minimum follow-up time of 6 months. To ensure that also PFS ‘on treatment’ has the desired accuracy, we accounted for 25% non-persistance due to toxicity, hence 105 patients. On top of these 105 patients, another 25 patients may be included, if they harbor rare PIK3CA mutations. Further information Corresponding author: sequel@nki.nl BOOG Study Center acts as sponsor for this trial. This trial is funded by Novartis.

Citation Format: Cornelia AM Almekinders, Inge RHM Konings, Vincent van der Noort, Susan M van den Berg, Monique EMM Bos, Vincent O Dezentjé. SEQUence of Endocrine therapy in advanced Luminal Breast cancer (SEQUEL-Breast): A phase 2 study on fulvestrant beyond progression in combination with alpelisib for PIK3CA-mutated, HR+ HER2- advanced breast cancer. [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr OT2-01-08.

Novel [1,5] sigmatropic rearrangements of cyclohexadienones generated from Fischer carbene complexes. A new strategy for installing the C-20 angular ethyl group in Aspidospermidine alkaloids

[formula: see text] We report here the first examples of a [1,5] sigmatropic rearrangement in a 4a-alkyl-4a-hydrocarbazol-4-one to yield a 3-alkylcarbazol-4-one with a re-aromatized indole nucleus. The reaction of 1-methyl-3-substituted-indole-2-carbene complexes 1 with terminal alkynes yields 3,4a-dialkyl-1-methoxy-9-methylcarbazol-4-ones 2. These 4a-substituted carbazolones thermally rearrange to cleanly give the more highly aromatic 3,3-dialkyl-1-methoxy-9-methylcarbazol-4-ones 3. This reaction provides a convenient entry to the Aspidosperma family of alkaloids, which contain a 3,3-disubstituted carbazole nucleus.

Evaluation of retinoid lactones as topical therapeutic agents in dermatology

PURPOSE

Optimization of the therapeutic ratio of analogs of the topically active 11-cis, 13-cis-12-hydroxymethylretinoic acid, delta-lactone (1) relative to antihyperproliferation and antihyperkeratinization vs. toxicity.

METHODS

Nine analogs of 1, in which variations were made in the lipophilic cyclohexenyl moiety or in the lactone ring, were evaluated for topical activity against hyperkeratinization, inhibition of TPA-induced DNA synthesis and for skin irritation.

RESULTS

Although more potent lactones than the parent lactone 1 were identified, none possessed the favorable therapeutic ratio associated with 1.

CONCLUSIONS

The delta-lactone 1 possesses unique molecular features responsible for its desirable therapeutic ratio as an antihyperproliferative and antihyperkeratotic agent. In view of its very low systemic retinoid toxicity and the absence of any systemic toxicity, this lactone may be a good candidate for use in the topical treatment of acne.

Evaluation of retinoids as therapeutic agents in dermatology

Evaluation of 13-cis-12-substituted analogues of retinoic acid in a series of dermatologic screens has revealed that structural modifications can lead to selectivity and specificity. An analogue, 11-cis,13-cis-12-hydroxymethylretinoic acid, delta-lactone, has been found to have good activity and to be devoid of topical and systemic toxicity.