Comparative efficacy and tolerability of the PARP inhibitors, olaparib 300 mg tablets BID, niraparib 300 mg capsules QD and rucaparib 600 mg tablets BID as maintenance treatment in BRCA -mutated ( BRCA m) platinum-sensitive relapsed ovarian

Small-molecule inhibitors, immune checkpoint inhibitors, and more: FDA-approved novel therapeutic drugs for solid tumors from 1991 to 2021

The United States Food and Drug Administration (US FDA) has always been a forerunner in drug evaluation and supervision. Over the past 31 years, 1050 drugs (excluding vaccines, cell-based therapies, and gene therapy products) have been approved as new molecular entities (NMEs) or biologics license applications (BLAs). A total of 228 of these 1050 drugs were identified as cancer therapeutics or cancer-related drugs, and 120 of them were classified as therapeutic drugs for solid tumors according to their initial indications. These drugs have evolved from small molecules with broad-spectrum antitumor properties in the early stage to monoclonal antibodies (mAbs) and antibody‒drug conjugates (ADCs) with a more precise targeting effect during the most recent decade. These drugs have extended indications for other malignancies, constituting a cancer treatment system for monotherapy or combined therapy. However, the available targets are still mainly limited to receptor tyrosine kinases (RTKs), restricting the development of antitumor drugs. In this review, these 120 drugs are summarized and classified according to the initial indications, characteristics, or functions. Additionally, RTK-targeted therapies and immune checkpoint-based immunotherapies are also discussed. Our analysis of existing challenges and potential opportunities in drug development may advance solid tumor treatment in the future.

Maintenance therapy for newly diagnosed epithelial ovarian cancer- a review

Epithelial ovarian cancer (EOC) is the most lethal gynaecological cancer among women worldwide, with the 5-year survival rate ranging between 30 and 40%. Due to the asymptomatic nature of the condition, it is more likely to be diagnosed at an advanced stage, requiring an aggressive therapeutic approach. Cytoreductive surgery (CRS) along with systemic chemotherapy with paclitaxel and carboplatin has been the mainstay of the treatment in the frontline management of EOC. In recent years, neo-adjuvant chemotherapy, followed by interval CRS has become an important strategy for the management of advanced EOC. Due to the high rate of recurrence, the oncology community has begun to shift its focus to molecular-targeted agents and maintenance therapy in the frontline settings. The rationale for maintenance therapy is to delay the progression or relapse of the disease, as long as possible after first-line treatment, irrespective of the amount of residual disease. Tumours with homologous recombination deficiency (HRD) including BReast CAncer gene (BRCA) mutations are found to be sensitive to polyadenosine diphosphate-ribose polymerase (PARP) inhibitors and understanding of HRD status has become important in the frontline setting. PARP inhibitors are reported to provide a significant improvement in progression-free survival and have an acceptable safety profile. PARP inhibitors have also been found to act regardless of BRCA status. Recently, PARP inhibitors as maintenance therapy in the frontline settings showed encouraging results in EOC; however, the results from further trials and survival data from ongoing trials are awaited for understanding the role of this pathway in treatment of EOC. This review discusses an overview of maintenance strategies in newly diagnosed EOC along with considerations for maintenance therapy in EOC with a focus on PARP inhibitors.

Utilization of Poly(ADP-Ribose) Polymerase Inhibitors in Ovarian Cancer: A Retrospective Cohort Study of US Healthcare Claims Data

Introduction

We aimed to characterize real-world utilization of poly(ADP-ribose) polymerase (PARP) inhibitors (PARPi) in women with ovarian cancer (OC).

Methods

This retrospective observational study of claims data from US MarketScan^® Commercial/Medicare Supplemental databases included women with OC initiating olaparib, niraparib, or rucaparib from January 1, 2017, to May 31, 2019. Patients were observed from first outpatient prescription until at least 30 days’ follow-up. Clinical events of interest (CEIs), based on adverse reactions in PARPi prescribing information, were identified from claims using ICD-9/10 codes. Other outcomes included dose modification, persistence, adherence, healthcare resource utilization (HCRU), and cost.

Results

Overall, 303, 348, and 162 women with OC received olaparib, niraparib, and rucaparib, respectively. During follow-up, risk of any CEI was higher with niraparib versus olaparib (odds ratio 3.36 [95% confidence interval 2.00–5.65]) and niraparib versus rucaparib (2.09 [1.10–3.95]), with no significant difference between rucaparib and olaparib (1.61 [0.93–2.79]). PARPi dose decreases were observed in 21.1%, 35.1%, and 30.2% of olaparib-, niraparib-, and rucaparib-treated patients, respectively. Persistence (no treatment gaps of more than 90 days) was significantly higher (P < 0.05) with olaparib (62.2%) versus niraparib (35.9%) and rucaparib (48.7%); adherence (medication possession ratio, MPR ≥ 80%) was 80.2% versus 38.6% and 63.2%, respectively (P < 0.001). Inpatient admissions and outpatient service use were higher with niraparib and rucaparib versus olaparib, reflected in mean (± standard deviation) total medical costs (excluding pharmacy) of $5393 ± 8828 for olaparib, $7732 ± 14,054 for niraparib, and $6868 ± 7929 for rucaparib.

Conclusion

Differences between the licensed PARPi were observed in the risk of experiencing a CEI, likelihood of dose modifications, ability to receive continuous PARPi therapy, HCRU, and costs.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12325-021-01959-5.

Decision analysis for secondline maintenance treatment of platinum sensitive recurrent ovarian cancer: a review

Most women with ovarian cancer experience disease relapse, presenting numerous treatment challenges for clinicians. Maintenance therapy in the relapsed setting aims to extend the time taken for a cancer to progress, thus delaying the need for additional treatments. Four therapies are currently approved in the USA for secondline maintenance treatment of platinum sensitive, recurrent ovarian cancer: one antivascular endothelial growth factor agent (bevacizumab) and three poly(adenosine diphosphate-ribose) polymerase (PARP) inhibitors (olaparib, niraparib, and rucaparib). In addition to efficacy, maintenance therapies must have a good tolerability profile and no significant detrimental impact on quality of life, as patients who receive maintenance are generally free from cancer related symptoms. Data from key bevacizumab trials (OCEANS, NCT00434642; GOG-0213, NCT00565851; MITO16B, NCT01802749) and PARP inhibitor trials (Study 19, NCT00753545; SOLO2, NCT01874353; NOVA, NCT01847274; ARIEL3, NCT01968213) indicate that bevacizumab and the PARP inhibitors are effective in patients with platinum sensitive, recurrent ovarian cancer but differ in their tolerability profiles. In addition, the efficacy of PARP inhibitors is dependent on the presence of homologous recombination repair deficiency, with patients with the deficiency experiencing greater responses from treatment compared with those who are homologous recombination repair proficient. Allowing for caveats of cross trial comparisons, we advise that clinicians account for the following points when choosing whether and when to administer a secondline maintenance treatment for a specific patient: presence of a homologous recombination repair deficient tumor; the patient's baseline characteristics, such as platelet count and blood pressure; mode of administration of therapy; and consideration of future treatment options for thirdline and later therapy.