Synthesis of calix (4) resorcinarene based amphiphilic macrocycle as an efficient nanocarrier for Amphotericin-B to enhance its oral bioavailability

The supramolecular-based macrocyclic amphiphiles have fascinating attention and find extensive utilization in the pharmaceutical industry for efficient drug delivery. In this study, we designed and synthesized a new supramolecular amphiphilic macrocycle to serve as an efficient nanocarrier, achieved by treating 4-hydroxybenzaldehyde with 1-bromotetradecane. The derivatized product was subsequently treated with resorcinol to cyclize, resulting in the formation of a calix(4)-resorcinarene-based supramolecular amphiphilic macrocycle. The synthesized macrocycle and intermediate products were characterized using mass spectrometry, IR, and 1H NMR spectroscopic techniques. The amphotericin-B (Amph-B)-loaded and unloaded amphiphiles were screened for biocompatibility studies, vesicle formation, particle shape, size, surface charge, drug entrapment, in-vitro release profile, and stability through atomic force microscopy (AFM), Zetasizer, HPLC, and FT-IR. Amph-B -loaded macrocycle-based niosomal vesicles were investigated for in-vivo bioavailability in rabbits. The synthesized macrocycle exhibited no cytotoxicity against normal mouse fibroblast cells and was found to be hemocompatible and safe in mice following an acute toxicity study. The drug-loaded macrocycle-based vesicles appeared spherical, nano-sized, and homogeneous in size, with a notable negative surface charge. The vesicles remained stable after 30 days of storage. The results of Amph-B oral bioavailability and pharmacokinetics revealed that the newly tailored niosomal formulation enhanced drug solubility, protected drug degradation at gastric pH, facilitated sustained drug release at the specific target site, and delayed plasma drug clearance. Incorporating such advanced niosomal formulations in the field of drug delivery systems has the potential to revolutionize therapeutic outcomes and improve the quality of patient well-being.

Abstract PD5-09: Fulvestrant for hormone receptor-positive advanced breast cancer in patients with visceral vs non-visceral metastases: Findings from FALCON, FIRST, and CONFIRM

BACKGROUND

Patients with hormone receptor-positive (HR+) locally advanced or metastatic breast cancer (LA/MBC) and non-visceral metastases (non-VM) generally have a better prognosis than patients with visceral metastases (VM). However, in the absence of visceral crisis, endocrine therapy (ET) remains an effective treatment option in both patient groups. This descriptive analysis examined the treatment effect of fulvestrant 500 mg vs comparators in postmenopausal patients with HR+ LA/MBC, with or without VM.

METHODS

Three randomized studies of fulvestrant 500 mg for postmenopausal HR+ LA/MBC were included. The Phase 3 FALCON study (NCT01602380) compared fulvestrant 500 mg with anastrozole in patients without any prior ET (n=462; fulvestrant 500 mg: 58.7% with VM; anastrozole: 51.3% with VM). The Phase 2 FIRST study (NCT00274469) compared fulvestrant 500 mg with anastrozole in patients who had not received ET for advanced disease (n=205; fulvestrant 500 mg: 47.1% with VM; anastrozole: 56.3% with VM). The Phase 3 CONFIRM study (NCT00099437) compared fulvestrant 500 mg with fulvestrant 250 mg (n=736; fulvestrant 500 mg: 56.6% with VM; fulvestrant 250 mg: 52.9% with VM); patients had received prior ET for adjuvant/advanced disease. The treatment effect of fulvestrant 500 mg vs comparator ET was determined using log-rank tests.

RESULTS

In FALCON, there was a greater treatment effect with fulvestrant 500 mg vs anastrozole for progression-free survival (PFS) in the non-VM group (hazard ratio [HR] 0.59) vs the VM group (HR 0.99). A consistent treatment effect was observed for fulvestrant 500 mg vs comparator for PFS in FIRST (non-VM HR 0.58; VM HR 0.82) and CONFIRM (non-VM HR 0.72; VM HR 0.86). Median PFS of fulvestrant 500 mg vs comparator in non-VM and VM subgroups was: 22.3 months (m) vs 13.8 m and 13.8 m vs 15.9 m, respectively, in FALCON; 34.0 m vs 21.3 m and 9.8 m vs 9.9 m in FIRST; and 10.4 m vs 5.9 m and 4.7 m vs 4.0 m in CONFIRM.

Clinical benefit rate with fulvestrant 500 mg vs anastrozole in FALCON was 87.4% vs 75.2% in the non-VM group, and 71.9% vs 73.1% in the VM group.

Overall survival (OS) in FALCON (31% maturity) showed a greater treatment effect with fulvestrant 500 mg vs anastrozole in the non-VM group vs the VM group (HR 0.60 vs 1.09). In terms of OS, in FIRST there was a greater treatment effect with fulvestrant 500 mg vs anastrozole in the non-VM group compared with the VM group (HR 0.68 vs 0.86). In CONFIRM, improved OS was observed with fulvestrant 500 mg vs fulvestrant 250 mg; this treatment effect was consistent in non-VM (HR 0.78) and VM subgroups (HR 0.83).

CONCLUSIONS

In three studies, an improved treatment effect of fulvestrant 500 mg vs comparator ET for HR+ LA/MBC was observed in patients with non-VM. The treatment effect of fulvestrant 500 mg vs comparator for PFS across all three studies appeared consistent. A reduced treatment effect of fulvestrant 500 mg vs comparator was generally seen in patients with VM, although fulvestrant 500 mg was still as effective as, or slightly more effective than, the comparator. These data suggest that patients without VM may benefit more from fulvestrant 500 mg than patients with VM.

Citation Format: Roberston JFR, Di Leo A, Fazal M, Lichfield J, Ellis MJ. Fulvestrant for hormone receptor-positive advanced breast cancer in patients with visceral vs non-visceral metastases: Findings from FALCON, FIRST, and CONFIRM [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr PD5-09.

Abstract P2-08-09: Progression-free survival results in postmenopausal Asian women: Subgroup analysis from a phase 3 randomized trial of fulvestrant 500 mg vs anastrozole for hormone receptor-positive advanced breast cancer (FALCON)

BACKGROUND

Fulvestrant is a selective estrogen receptor degrader (SERD) with no known agonist effects. In the open-label Phase 2 FIRST study, fulvestrant 500 mg suggested improved efficacy as first-line treatment vs anastrozole in patients with hormone receptor-positive locally advanced or metastatic breast cancer (LA/MBC). The Phase 3, randomized, double-blind, multicenter FALCON trial (NCT01602380) compared fulvestrant 500 mg with anastrozole 1 mg in patients with hormone receptor-positive LA/MBC who had not received prior hormonal therapy. The primary endpoint of the study, progression-free survival (PFS) assessed via RECIST 1.1, surgery/radiotherapy for disease worsening, or death (any cause), was met, as shown by a statistically significant improvement in PFS for fulvestrant 500 mg vs anastrozole. This analysis evaluated PFS in the Asian patient subgroup, which included all randomized patients from centers in China, Japan, and Taiwan.

METHODS

Eligible patients had ER and/or progesterone receptor-positive breast cancer, WHO performance status 0–2, and ≥1 measurable/non-measurable lesion(s). Patients were randomized (1:1) to receive fulvestrant 500 mg (IM on Days 0, 14, 28, and each 28 days thereafter) or anastrozole 1 mg daily, and were stratified according to LA or MBC; prior or no prior treatment with chemotherapy for LA/MBC; and measurable or non-measurable disease. The consistency of effect across patient subgroups was assessed via hazard ratios and 95% confidence intervals using a log-rank test.

RESULTS

In total, 462 patients were randomized (n=230 fulvestrant 500 mg; n=232 anastrozole). The Asian subgroup comprised 67 patients (n=34 fulvestrant 500 mg; n=33 anastrozole). PFS outcomes for the Asian and non-Asian subgroups are presented (Table). The most commonly reported adverse event (AE) was arthralgia (18.2% vs 12.1% of patients with fulvestrant 500 mg and anastrozole, respectively). The rate of AEs leading to discontinuation of treatment was 3.0% and 3.0%, respectively.

CONCLUSIONS

Based on a preliminary assessment of 67 patients, the treatment effect in the Asian patient subgroup from the FALCON trial appears to be broadly consistent with the non-Asian population.

PFS in Asian and non-Asian patient subgroupsGeographic regionNumber of patients (%) with event Hazard ratio (95% CI) Fulvestrant 500 mg n=230Anastrozole n=232 Asia19/34 (55.9%)22/33 (66.7%)0.81 (0.44, 1.50)Non-Asia124/196 (63.3%)144/199 (72.4%)0.79 (0.62, 1.01)

Citation Format: Shao Z, Ellis MJ, Robertson JFR, Grinsted LM, Fazal M, Noguchi S. Progression-free survival results in postmenopausal Asian women: Subgroup analysis from a phase 3 randomized trial of fulvestrant 500 mg vs anastrozole for hormone receptor-positive advanced breast cancer (FALCON) [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-08-09.

Abstract P2-08-02: Progression-free survival results in patient subgroups from a Phase 3 randomized trial of fulvestrant 500 mg vs anastrozole for hormone receptor-positive advanced breast cancer (FALCON)

BACKGROUND

Improved efficacy was suggested for fulvestrant 500 mg, a selective estrogen receptor degrader (SERD), vs anastrozole as first-line treatment for hormone receptor-positive locally advanced or metastatic breast cancer (LA/MBC) in the open-label Phase 2 FIRST trial. The Phase 3, randomized, double-blind, multicenter FALCON trial (NCT01602380) compared fulvestrant 500 mg with anastrozole 1 mg in patients with hormone receptor-positive LA/MBC who had not received prior hormonal therapy. The primary endpoint of the study was met, such that there was a statistically significant improvement in progression-free survival (PFS) for fulvestrant 500 mg vs anastrozole. We present an analysis of PFS for pre-specified patient subgroups in the FALCON trial.

METHODS

Eligible patients had ER and/or progesterone receptor (PgR)-positive breast cancer, WHO performance status 0–2 and ≥1 measurable/non-measurable lesion(s). Patients were randomized (1:1) to receive fulvestrant 500 mg (IM on Days 0, 14, 28, and each 28 days thereafter) or anastrozole 1 mg daily. The primary endpoint was PFS, assessed via RECIST 1.1, surgery/radiotherapy for disease worsening, or death (any cause). PFS was evaluated in patient subgroups defined by pre-specified baseline covariates. The consistency of effect across patient subgroups was assessed via hazard ratios and 95% confidence intervals using a log-rank test.

RESULTS

Overall, 462 patients were randomized to treatment: 230 received fulvestrant 500 mg and 232 received anastrozole. PFS outcomes in each patient subgroup are presented in the Table.

CONCLUSIONS

This analysis of patient subgroups from the FALCON trial suggests that treatment effects were largely consistent across the subgroups analyzed with some possible exceptions (e.g. patients with visceral vs non-visceral disease). Further work is ongoing to understand the possible treatment effect in these subgroups.

PFS in pre-specified patient subgroupsSubgroup Number of patients (%) with event Hazard ratio (95% CI)  Fulvestrant 500 mg n=230 Anastrozole n=232 Breast cancer type   Locally advanced11/28 (39.3%)14/32 (43.8%)0.79 (0.36, 1.73)Metastatic132/202 (65.3%)152/200 (76.0%)0.78 (0.62, 0.99)Prior chemotherapy for LA/MBC   Yes31/36 (86.1%)33/43 (76.7%)1.08 (0.66, 1.77)No112/194 (57.7%)133/189 (70.4%)0.75 (0.59, 0.97)Geographic regiona   US/Canada16/25 (64.0%)19/24 (79.2%)0.66 (0.34, 1.30)Non-US/Canada127/205 (62.0%)147/208 (70.7%)0.81 (0.64, 1.03)Measurable disease   Yes124/193 (64.2%)143/196 (73.0%)0.76 (0.60, 0.97)No19/37 (51.4%)23/36 (63.9%)0.99 (0.53, 1.82)ER-positive and PgR-positive   Yes103/175 (58.9%)127/179 (70.9%)0.73 (0.56, 0.94)No40/55 (72.7%)39/53 (73.6%)1.04 (0.67, 1.62)Bisphosphonate use at baseline   Yes44/61 (72.1%)53/62 (85.5%)0.69 (0.46, 1.03)No99/169 (58.6%)113/170 (66.5%)0.82 (0.63, 1.07)Visceral disease   Yes92/135 (68.1%)87/119 (73.1%)0.99 (0.74, 1.33)No51/95 (53.7%)79/113 (69.9%)0.59 (0.42, 0.84)ªData for Asia/non-Asia subgroups are presented in a separate abstract

Citation Format: Robertson JFR, Noguchi S, Shao Z, Grinsted LM, Fazal M, Ellis MJ. Progression-free survival results in patient subgroups from a Phase 3 randomized trial of fulvestrant 500 mg vs anastrozole for hormone receptor-positive advanced breast cancer (FALCON) [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-08-02.

Colloid cyst of the third ventricle--a neurological emergency

Colloid cyst of the third ventricle, although a benign lesion, carries with it high mortality and morbidity if not diagnosed in time. The most common presenting symptom is headache. A 31-year-old man with a history of intermittent, throbbing, unilateral headache and nausea was admitted because of exacerbation of his headache, which responded poorly to medication. A few hours after admission he became comatose. A colloid cyst of the third ventricle causing acute hydrocephaly was diagnosed by computed tomographic scan and removed in toto. Despite an uneventful postoperative course the patient was left with permanent bilateral cerebral damage. In patients with headache not responding to conventional medication, colloid cyst of the third ventricle perhaps should be ruled out, even if the symptoms are suggestive of vascular headache, such as migraine headache.