A phase II study of sequential neoadjuvant gemcitabine plus doxorubicin followed by gemcitabine plus cisplatin in patients with operable breast cancer: prediction of response using molecular profiling

This study examined the pathological complete response (pCR) rate and safety of sequential gemcitabine-based combinations in breast cancer. We also examined gene expression profiles from tumour biopsies to identify biomarkers predictive of response. Indian women with large or locally advanced breast cancer received 4 cycles of gemcitabine 1200 mg m−2 plus doxorubicin 60 mg m−2 (Gem+Dox), then 4 cycles of gemcitabine 1000 mg m−2 plus cisplatin 70 mg m−2 (Gem+Cis), and surgery. Three alternate dosing sequences were used during cycle 1 to examine dynamic changes in molecular profiles. Of 65 women treated, 13 (24.5% of 53 patients with surgery) had a pCR and 22 (33.8%) had a complete clinical response. Patients administered Gem d1, 8 and Dox d2 in cycle 1 (20 of 65) reported more toxicities, with G3/4 neutropenic infection/febrile neutropenia (7 of 20) as the most common cycle-1 event. Four drug-related deaths occurred. In 46 of 65 patients, 10-fold cross validated supervised analyses identified gene expression patterns that predicted with ⩾73% accuracy (1) clinical complete response after eight cycles, (2) overall clinical complete response, and (3) pCR. This regimen shows strong activity. Patients receiving Gem d1, 8 and Dox d2 experienced unacceptable toxicity, whereas patients on other sequences had manageable safety profiles. Gene expression patterns may predict benefit from gemcitabine-containing neoadjuvant therapy

Whole cell screen based identification of spiropiperidines with potent antitubercular properties

Abstract Whole cell based screens to identify hits against Mycobacterium tuberculosis (Mtb), carried out under replicating and non-replicating (NRP) conditions, resulted in the identification of multiple, novel but structurally related spiropiperidines with potent antitubercular properties. These compounds could be further classified into three classes namely 3-(3-aryl-1,2,4-oxadiazol-5-yl)-1′-alkylspiro[indene-1,4′-piperidine] (abbr. spiroindenes), 4-(3-aryl-1,2,4-oxadiazol-5-yl)-1′-alkylspiro[chromene-2,4′-piperidine] (abbr. spirochromenes) and 1′-benzylspiro[indole-1,4′-piperidin]-2(1H)-one (abbr. spiroindolones). Spiroindenes showed ≥4 log10 kill (at 2-12 μM) on replicating Mtb, but were moderately active under non replicating conditions. Whole genome sequencing efforts of spiroindene resistant mutants resulted in the identification of I292L mutation in MmpL3 (Mycobacterial membrane protein Large), required for the assembly of mycolic acid into the cell wall core of Mtb. MIC modulation studies demonstrated that the mutants were cross-resistant to spirochromenes but not to spiroindolones. This Letter describes lead identification efforts to improve potency while reducing the lipophilicity and hERG liabilities of spiroindenes. Additionally, as deduced from the SAR studies, we provide insights regarding the new chemical opportunities that the spiroindolones can offer to the TB drug discovery initiatives