PARP Inhibitors: Extending Benefit Beyond BRCA-Mutant Cancers.

A mounting body of evidence now indicates that PARP inhibitors have the potential to be used as a foundation for both monotherapy and combination strategies across a wide spectrum of molecular backgrounds and tumor types. Although PARP inhibitors as a class display many similarities, critical differences in structure can translate into differences in tolerability and antitumor activity that have important implications for the clinic. Furthermore, while PARP inhibitors have demonstrated a clear role in treating tumors with underlying homologous recombination deficiencies, there is now biological and early clinical evidence to support their use in other molecular subsets of cancer, including tumors associated with high levels of replication stress such as small-cell lung cancer. In this article, we highlight the key similarities and differences between individual PARP inhibitors and their implications for the clinic. We discuss data that currently support clinical strategies for extending the benefit of PARP inhibitors beyond BRCA-mutant cancers, toward broader populations of patients through the use of novel biomarkers of homologous recombination repair deficiency (HRD), as well as predictive biomarkers rooted in mechanisms of sensitivity outside of HRD. We also explore the potential application of PARP inhibitors in earlier treatment settings, including neoadjuvant, adjuvant, and even chemoprevention approaches. Finally, we focus on promising combination therapeutic strategies, such as those with other DNA damage response (DDR) inhibitors such as ATR inhibitors, immune checkpoint inhibitors, and non-DDR-targeted agents that induce "chemical BRCAness."

The role of afatinib in the management of non-small cell lung carcinoma.

INTRODUCTION: Despite initial patient benefit, drug resistance to first-generation EGFR tyrosine kinase inhibitors (TKIs) is inevitable. One of the key mechanisms responsible for the development of acquired drug resistance is the secondary T790M missense mutation in exon 20 of the EGFR kinase domain. Afatinib is an ATP-competitive small molecule inhibitor that potently and irreversibly inhibits EGFR and mutated EGFR including the T790M variant, as well as other members of the ErbB family in preclinical studies. AREAS COVERED: The authors describe the rationale and provide the preclinical background to afatinib and its potential as a NSCLC therapy. Specifically, the authors detail the drug's pharmaco-kinetic profile and review its clinical efficacy and toxicity profile. EXPERT OPINION: Afatinib is an effective treatment option for therapy-naive advanced NSCLC harboring an activating EGFR mutation. Furthermore, it is also of potential benefit to patients with acquired resistance to EGFR kinase inhibitors. In the future, the authors envision the clinical development of third-generation EGFR mutation-specific inhibitors in NSCLC, which may potentially spare normal tissue toxicity. Nevertheless, afatinib currently represents a bona fide treatment option in the NSCLC therapeutic armamentarium.

Cabazitaxel in metastatic castration-resistant prostate cancer.

Metastatic castration-resistant prostate cancer (CRPC) has a poor prognosis and remains a significant therapeutic challenge. Prior to 2010, docetaxel chemotherapy was the only treatment shown to improve overall survival, symptom control and quality of life in patients with CRPC. Research efforts focused on overcoming chemoresistance to taxanes eventually led to the development of multiple novel anti-tumor agents, including cabazitaxel. Cabazitaxel has recently been shown to significantly improve overall survival compared with mitoxantrone in a large multicenter Phase III study. This article details the preclinical and clinical development of cabazitaxel and discusses the importance of this novel chemotherapy in CRPC. The authors also discuss the challenges now facing the future use of cabazitaxel in CRPC, including the determination of the optimal dose of cabazitaxel in patients with advanced CRPC, the ideal sequencing of cabazitaxel relative to other anti-tumor treatments, appropriate patient selection and novel strategies for the assessment of treatment response.