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This review highlights strategies to integrate dose optimization into premarketing drug development and discusses the underlying statistical principles. Poor dose optimization can have negative consequences for patients, most commonly because of toxicity, including poor quality of life, reduced effectiveness because of inability of patients to stay on current therapy or receive subsequent therapy because of toxicities, and difficulty in developing combination regimens. We reviewed US Food and Drug Administration initial approvals (2019-2021) of small molecules and antibody-drug conjugates for oncologic indications to determine the proportion with a recommended dosage at the maximum tolerated dose or the maximal administered dose, to characterize the use of randomized evaluations of multiple dosages in dose selection, to describe the frequency of dose modifications at the recommended dosage, and to identify case examples that highlight key principles for premarket dose optimization during drug development. Herein, we highlight major principles for dose optimization and review examples of recent US Food and Drug Administration approvals that illustrate how investigation of dose- and exposure-response relationships and use of randomized dose trials can support dose optimization. Although there has been some progress, dose optimization through randomized dose evaluation in oncology trials is not routinely conducted. Dose optimization is essential to ensure that patients receive therapies which maximize efficacy while minimizing toxicity.

On November 14, 2022, the U.S. Food and Drug Administration (FDA) granted accelerated approval to mirvetuximab soravtansine-gynx for treatment of adult patients with folate receptor-α (FRα)-positive, platinum-resistant epithelial ovarian, fallopian tube or primary peritoneal cancer who have received one to three prior systemic therapies. The VENTANA FOLR1 (FOLR-2.1) RxDx Assay was approved as a companion diagnostic device to select patients for this indication. Approval was based on Study 0417 (SORAYA, NCT04296890), a single-arm, multicenter trial. In 104 patients with measurable disease who received mirvetuximab soravtansine-gynx, the overall response rate was 31.7% (95% CI: 22.9, 41.6) with a median duration of response of 6.9 months (95% CI: 5.6, 9.7). Ocular toxicity was included as a Boxed Warning in the U.S. Prescribing Information (USPI) to alert providers of the risks of developing severe ocular toxicity including vision impairment and corneal disorders. Pneumonitis and peripheral neuropathy were additional important safety risks included as Warnings and Precautions in the USPI. This is the first approval of a targeted therapy for FRα-positive, platinum-resistant ovarian cancer and the first antibody-drug conjugate approved for ovarian cancer. This article summarizes the favorable benefit-risk assessment leading to FDA’s approval of mirvetuximab soravtansine-gynx.

Purpose:Cancer clinical trials often accrue slowly or miss enrollment targets. Strict eligibility criteria are a major reason. Restrictive criteria also limit opportunities for patient participation while compromising external validity of trial results. We examined the impact of broadening select eligibility criteria on characteristics and number of patients eligible for trials, using recommendations of the American Society of Clinical Oncology (ASCO) and Friends of Cancer Research.Experimental Design:A retrospective, observational analysis used electronic health record data from ASCO’s CancerLinQ Discovery database. Study cohort included patients with advanced non–small cell lung cancer treated from 2011 to 2018. Patients were grouped by traditional criteria [no brain metastases, no other malignancies, and creatinine clearance (CrCl) ≥ 60 mL/minute] and broadened criteria (including brain metastases, other malignancies, and CrCl ≥ 30 mL/minute).Results:The analysis cohort included 10,500 patients. Median age was 68 years, and 73% of patients were White. Most patients had stage IV disease (65%). A total of 5,005 patients (48%) would be excluded from trial participation using the traditional criteria. The broadened criteria, however, would allow 98% of patients (10,346) to be potential participants. Examination of patients included by traditional criteria (5,495) versus those added (4,851) by broadened criteria showed that the number of women, patients aged 75+ years, and those with stage IV cancer was significantly greater using broadened criteria.Conclusions:This analysis of real-world data demonstrated that broadening three common eligibility criteria has the potential to double the eligible patient population and include trial participants who are more representative of those encountered in practice.See related commentary by Giantonio, p. 2369

Tables of ICD9 and ICD10 codes used.

Summary Background Cyclin-dependent kinase 4/6 inhibitors (CDKIs) are oral targeted agents approved for use in combination with endocrine therapy as first-line or second-line treatment of patients with hormone receptor-positive, HER2-negative, advanced or metastatic breast cancer. We previously reported the pooled analyses of progression-free survival in patients in specific clinicopathological subgroups, all of whom received consistent benefit from the addition of a CDKI to hormonal therapy. Here, we report the pooled overall survival results in patients treated with a CDKI and fulvestrant. Methods In this exploratory analysis, we pooled individual patient data from three phase 3 randomised trials of CDKI or placebo in combination with fulvestrant in patients with breast cancer submitted to the US Food and Drug Administration and approved before Aug 1, 2020, in support of marketing applications. All analysed patients were aged at least 18 years, had an Eastern Cooperative Oncology Group performance status of 0–1, had hormone receptor-positive, HER2-negative advanced or metastatic breast cancer, and received at least one dose of CDKI or placebo in combination with fulvestrant. The median overall survival was estimated using Kaplan-Meier methods, and hazard ratios (HRs) with corresponding 95% CIs were estimated using Cox regression models. Patients were analysed collectively, by number of previous lines of systemic endocrine therapy in any disease setting (first-line or endocrine naive vs second-line and later), and in various clinicopathological subgroups of interest. The estimated median overall survival was not reported by group when the pooled population included patients treated across lines of therapy because of potential patient heterogeneity. All results presented are considered exploratory and hypothesis generating. Findings Across the three pooled trials, 1960 patients were randomly assigned between Oct 7, 2013, and June 10, 2016 (12 patients were not treated and 1296 [66%] patients were randomly assigned to CDKI and 652 [33%] to placebo). In all treated patients (n=1948), the estimated HR for overall survival was 0·77 (95% CI 0·68–0·88), with a median follow-up of 43·7 months (IQR 37·8–47·7) and deaths in 935 (48%) of the 1948 patients. The difference in estimated median overall survival was 7·1 months, favouring CDKIs. In patients who received CDKIs or placebo in combination with fulvestrant as first-line systemic endocrine therapy (two trials; n=396), the estimated HR for overall survival was 0·74 (95% CI 0·52–1·07), with a median follow-up of 39·4 months (IQR 37·0–42·2). 123 (31%) of these patients died. The difference in estimated median overall survival could not be calculated because median overall survival was not estimable (95% CI 50·9–not estimable) in the CDKI group and was 45·7 months (95% CI 41·7–not estimable) in the placebo group. In patients who received CDKIs or placebo in combination with fulvestrant as second-line or later systemic endocrine therapy (three trials; n=1552), the estimated HR for overall survival was 0·77 (95% CI 0·67–0·89), with a median follow-up of 45·1 months (95% CI 39·2–48·5). 812 (52%) of these patients died. The difference in estimated median overall survival was 7·0 months, favouring CDKIs. Interpretation The addition of CDKIs to fulvestrant resulted in a consistent overall survival benefit in all pooled patients and within most clinicopathological subgroups of interest. These findings support the existing standard of care of CDKIs plus fulvestrant for the treatment of patients with hormone receptor-positive, HER2-negative, advanced breast cancer. Funding None.

Purpose: Restrictive clinical trial eligibility criteria (EC) limit the number of patients who can enroll and potentially benefit from protocol-driven, investigational treatment plans and reduce the generalizability of trial results to the broader population. Following publication of expert stakeholder recommendations for broadening EC in 2017, the American Society of Clinical Oncology (ASCO) and Friends of Cancer Research (Friends) convened working groups to produce additional recommendations and analyze the potential impact on clinical trials using real-world data. Experimental Design: Multistakeholder working groups were appointed by an ASCO-Friends leadership group to propose recommendations for more inclusive EC related to: washout periods, concomitant medications, prior therapies, laboratory reference ranges and test intervals, and performance status. Results: The four working groups, ASCO Board of Directors, and Friends leadership support the recommendations included in this statement to modernize EC related to washout periods, concomitant medications, prior therapies, laboratory references ranges and test intervals, and performance status to make trial populations more inclusive and representative of cancer patient populations. Conclusions: Implementation of the recommendations is intended to result in greater ease of determining patient eligibility. Increased opportunities for patient participation in research will help address longstanding underrepresentation of certain groups in clinical trials and produce evidence that is more informative for a broader patient population. More patients eligible will also likely speed clinical trial accrual. See related commentary by Giantonio, p. 2369

Purpose: Cancer clinical trials often accrue slowly or miss enrollment targets. Strict eligibility criteria are a major reason. Restrictive criteria also limit opportunities for patient participation while compromising external validity of trial results. We examined the impact of broadening select eligibility criteria on characteristics and number of patients eligible for trials, using recommendations of the American Society of Clinical Oncology (ASCO) and Friends of Cancer Research. Experimental Design: A retrospective, observational analysis used electronic health record data from ASCO’s CancerLinQ Discovery database. Study cohort included patients with advanced non–small cell lung cancer treated from 2011 to 2018. Patients were grouped by traditional criteria [no brain metastases, no other malignancies, and creatinine clearance (CrCl) ≥ 60 mL/minute] and broadened criteria (including brain metastases, other malignancies, and CrCl ≥ 30 mL/minute). Results: The analysis cohort included 10,500 patients. Median age was 68 years, and 73% of patients were White. Most patients had stage IV disease (65%). A total of 5,005 patients (48%) would be excluded from trial participation using the traditional criteria. The broadened criteria, however, would allow 98% of patients (10,346) to be potential participants. Examination of patients included by traditional criteria (5,495) versus those added (4,851) by broadened criteria showed that the number of women, patients aged 75+ years, and those with stage IV cancer was significantly greater using broadened criteria. Conclusions: This analysis of real-world data demonstrated that broadening three common eligibility criteria has the potential to double the eligible patient population and include trial participants who are more representative of those encountered in practice. See related commentary by Giantonio, p. 2369

Purpose: Restrictive eligibility criteria induce differences between clinical trial and “real-world” treatment populations. Restrictions based on prior therapies are common; minimizing them when appropriate may increase patient participation in clinical trials. Experimental Design: A multi-stakeholder working group developed a conceptual framework to guide evaluation of prevailing practices with respect to using prior treatment as selection criteria for clinical trials. The working group made recommendations to minimize restrictions based on prior therapies within the boundaries of scientific validity, patient centeredness, distributive justice, and beneficence. Recommendations: (i) Patients are eligible for clinical trials regardless of the number or type of prior therapies and without requiring a specific therapy prior to enrollment unless a scientific or clinically based rationale is provided as justification. (ii) Prior therapy (either limits on number and type of prior therapies or requirements for specific therapies before enrollment) could be used to determine eligibility in the following cases: a) the agents being studied target a specific mechanism or pathway that could potentially interact with a prior therapy; b) the study design requires that all patients begin protocol-specified treatment at the same point in the disease trajectory; and c) in randomized clinical studies, if the therapy in the control arm is not appropriate for the patient due to previous therapies received. (iii) Trial designers should consider conducting evaluation separately from the primary endpoint analysis for participants who have received prior therapies. Conclusions: Clinical trial sponsors and regulators should thoughtfully reexamine the use of prior therapy exposure as selection criteria to maximize clinical trial participation. See related commentary by Giantonio, p. 2369

Over the last decade, there has been tremendous progress in the treatment of patients with gynecologic cancers with a changing therapy landscape. This summary provides an overview of U.S. Food and Drug Administration (FDA) approvals for gynecologic cancers from 2010 to 2020, totaling 17 new indications. For each of the approved indications, endpoints, trial design, results, and regulatory considerations are outlined. Among these 17 indications, six received accelerated approval (AA) and 11 received regular approval (RA). As of September 2021, of the six AA, three have subsequently demonstrated clinical benefit resulting in conversion to RA and the remaining three have ongoing clinical trials that have not yet reported results. Approval decisions for these 17 indications were supported by primary efficacy endpoints of progression-free survival (n = 10), objective response rate (n = 6), and overall survival (n = 1) and showed a favorable benefit–risk profile. Among the 17 indications, 15 received priority review and three applications participated in one or more novel Oncology Center of Excellence initiatives, including Real Time Oncology Review, Assessment Aid, and Project Orbis. Current FDA thinking on drug development opportunities and regulatory initiatives currently under way will be discussed.

e24101 Background: Pain medications (PMs) are commonly used to treat pain in patients with advanced or metastatic breast cancer (MBC). We previously reported an initial analysis of PM prescribing patterns in clinical trial participants with breast cancer receiving CDK 4/6 inhibitor (CDKI)-based treatment. We present an updated analysis here. Methods: We pooled data from 7 randomized controlled trials of CDKI + endocrine therapy (ET) in patients with HR+, HER2-negative MBC. All analyzed patients received at least 1 dose of CDKI/placebo+ET and a concomitant PM with a documented start date. Medications administered during hospitalizations were not included. We looked at PM use in all patients, patients who took PM only before or after the trial started, and those who took PM both before and during the trial. PMs were categorized as opioid (includes codeine-containing), NSAIDS, or other (i.e. bone-directed, antiepileptic, topical PMs). Results: 4200 patients enrolled across the 7 trials who received at least one dose of CDKI/placebo+ET (n = 2616 CDKI, n = 1548 placebo). Of these, 2881 took a PM at any time (n = 1774 CDKI, n = 1107 placebo). Of the 1774 patients who received CDKI+ET, 487 (27%) took at least one opioid and one NSAID at any time, 782 (44%) took at least one NSAID at any time but no opioids, 244 (14%) took at least one opioid at any time but no NSAIDs, and 261 (15%) took only PM that were not opioids or NSAIDs. Of the 1107 patients who received placebo+ET, 297 (27%) took at least one opioid and one NSAID at any time, 490 (44%) took at least one NSAID at any time but no opioids, 153 (14%) took at least one opioid at any time but no NSAIDS, and 167 (15%) took only PM that were not opioids or NSAIDs. Of the 2881 patients who took a PM at any time, 2038 patients (n = 1222 CDKI, n = 816 placebo) had documented start for their PM. Of these, 544 took PM only before the trial started (n = 334 CDKI, n = 210 placebo), 915 took a PM only during the trial (n = 551 CDKI, n = 364 placebo), and 579 took a PM both before and during the trial (n = 337 CDKI, n = 242 placebo). Overall, more patients took NSAIDs only compared to opioids only. Patient characteristics at baseline were balanced between the two arms. Conclusions: Overall, PM prescribing patterns were similar between the arms. NSAID use was higher than opiates in all groups. These findings are hypothesis generating and additional research is needed to determine the impact of PM on participants’ pain and physical function. Further research should include an understanding of the duration of PM needed in patients with MBC.

Background: Cyclin dependent kinase 4/6 inhibitors (CDKIs) are oral targeted agents approved for use in combination with endocrine therapy as 1st or 2nd line treatment of hormone-receptor positive (HR+), human epidermal growth factor receptor 2 (HER2)-negative advanced or metastatic breast cancer. We previously reported the pooled analyses of progression-free survival (PFS) of patients in certain clinicopathological subgroups, all of whom received consistent benefit from the addition of a CDKI to hormonal therapy. Here, we report the pooled overall survival (OS) results in patients treated with a CDKI and fulvestrant. Methods: We pooled individual patient data (n=1948) from three phase III randomized breast cancer trials of CDKI in combination with fulvestrant submitted to the US Food and Drug Administration (FDA) in support of marketing applications. All analyzed patients received at least one dose of CDKI or placebo in combination with fulvestrant. The median OS was estimated using Kaplan-Meier (KM) methods, and hazard ratios (HR) with corresponding 95% confidence intervals (CIs) were estimated using Cox regression models. Patients were analyzed collectively, by number of prior lines of systemic endocrine therapy in any disease setting (1st-line or endocrine naive vs. 2nd -line and later), and in various clinicopathologic subgroups of interest. Findings: In all pooled patients (n=1948), the estimated OS HR was 0∙77 (95% CI 0∙68-0∙88), with a median follow-up of 43∙7 months (interquartile range, (IQR): 37∙8, 47∙7) and deaths in 48% of patients. The difference in estimated median OS was 7∙1 months, favoring CDKIs. In patients who were endocrine therapy naive and received CDKIs as 1st -line systemic endocrine therapy (2 trials, n=396), the estimated OS HR was 0∙74 (95% CI 0∙52-1∙07), with a median follow-up of 39∙4 months (IQR: 37∙0, 42∙2) and deaths in 31% of patients. The median OS difference could not be calculated, since median OS was not reached on CDKI arm. In patients who received CDKIs as 2nd-line or later systemic endocrine therapy (3 trials, n=1552), the estimated OS HR was 0∙77 (95% CI 0∙67-0∙89), with a median follow-up of 45∙1 months (IQR: 39∙2, 48∙5) and deaths in 52% of patients. The median OS difference was 7∙0 months, favoring CDKIs. Additional subgroup analyses of OS by progesterone receptor status, site of metastases, breast cancer histology, ECOG performance status, race, and de novo metastatic presentation all favored adding CDKI to fulvestrant. Patients with de novo metastatic disease (n=470, OS HR 0∙91 [95% CI 0∙68-1∙21]) and Asian patients (n=394, OS HR 0∙95 [95% CI 0∙81-1∙60]) appeared to benefit relatively less from the addition of CDKI to fulvestrant. Although the estimated OS HR appeared to favor fulvestrant alone in patients age < 40 [HR 1∙5 (95% CI 0∙75-3∙02)], this result must be interpreted with caution, given the small sample size (n=89) and correspondingly wide confidence interval. Evaluation of other age subgroups showed results in favor of the addition of CDKI to fulvestrant. All results presented are considered exploratory and hypothesis-generating. Interpretation: Addition of CDKIs to fulvestrant appears to confer a consistent overall survival benefit across all pooled patients and within most clinicopathological subgroups of interest. Funding: None. Declaration of Interest: All authors declare no competing interests. Ethical Approval: All patients in the included trials were required to provide informed written consent, and all trials had institutional review board or ethical approval.

Purpose The primary purposes of eligibility criteria are to protect the safety of trial participants and define the trial population. Excessive or overly restrictive eligibility criteria can slow trial accrual, jeopardize the generalizability of results, and limit understanding of the intervention’s benefit-risk profile. Methods ASCO, Friends of Cancer Research, and the US Food and Drug Administration examined specific eligibility criteria (ie, brain metastases, minimum age, HIV infection, and organ dysfunction and prior and concurrent malignancies) to determine whether to modify definitions to extend trials to a broader population. Working groups developed consensus recommendations based on review of evidence, consideration of the patient population, and consultation with the research community. Results Patients with treated or clinically stable brain metastases should be routinely included in trials and only excluded if there is compelling rationale. In initial dose-finding trials, pediatric-specific cohorts should be included based on strong scientific rationale for benefit. Later phase trials in diseases that span adult and pediatric populations should include patients older than age 12 years. HIV-infected patients who are healthy and have low risk of AIDS-related outcomes should be included absent specific rationale for exclusion. Renal function criteria should enable liberal creatinine clearance, unless the investigational agent involves renal excretion. Patients with prior or concurrent malignancies should be included, especially when the risk of the malignancy interfering with either safety or efficacy endpoints is very low. Conclusion To maximize generalizability of results, trial enrollment criteria should strive for inclusiveness. Rationale for excluding patients should be clearly articulated and reflect expected toxicities associated with the therapy under investigation.

1055 JJG, JC, TMP contributed equally. JAB, LAK contributed equally. Background: Cyclin dependent kinase 4/6 inhibitors (CDKIs) are oral targeted agents approved for use in combination with endocrine therapy as first or secondline treatment of hormone-receptor positive (HR+), human epidermal growth factor receptor 2 (HER2)-negative advanced or metastatic breast cancer. We previously reported the pooled analyses of progression-free survival of patients in certain clinicopathologic subgroups, and results showed a consistent benefit from the addition of a CDKI to endocrine therapy. Here, we report the pooled overall survival (OS) results in patients treated with a CDKI plus fulvestrant. Methods: We pooled individual patient data (n=1948) from three phase III randomized breast cancer trials of a CDKI plus fulvestrant submitted to the FDA in support of marketing applications. All analyzed patients received at least one dose of a CDKI or placebo, plus fulvestrant. The median OS was estimated using Kaplan-Meier (KM) methods, and hazard ratios (HR) with corresponding 95% confidence intervals (CIs) were estimated using Cox regression models. Results: Results of OS analyses, including all pooled patients, patients treated in the first-line setting, and patients treated in the second line and later settings, are summarized in the table below. Additional subgroup analyses of OS by progesterone receptor status, site of metastases, breast cancer histology, ECOG performance status, race, and de novo metastatic presentation all favored adding a CDKI to fulvestrant. In patients age < 40, the estimated OS HR favored fulvestrant alone, but this subgroup had a small sample size (n=89), so this result must be interpreted with caution. All results are considered exploratory and hypothesis-generating. Conclusions: Addition of CDKIs to fulvestrant appears to confer a consistent survival benefit across all pooled patients and within most clinicopathological subgroups of interest.[Table: see text]

Historically, oncology clinical trials have focused on comparing a new drug’s efficacy to the standard of care. However, as our understanding of molecular pathways in oncology has evolved, so has our ability to predict how patients will respond to a particular drug, and thus comparison with a standard therapy has become less important. Biomarkers and corresponding diagnostic testing are becoming more and more important to drug development but also limit the type of patient who may benefit from the therapy. Newer clinical trial designs have been developed to assess clinically meaningful endpoints in biomarker-enriched populations, and the number of modern, molecularly driven clinical trials are steadily increasing. At the same time, barriers to clinical trial enrollment have also grown. Many barriers contribute to nonenrollment in clinical trials, including patient, physician, institution, protocol, and regulatory barriers. At the protocol level, eligibility criteria have become a large roadblock to clinical trial accrual. Over time, eligibility criteria have become more and more restrictive. To accrue an adequate number of patients to molecularly driven trials, we should consider eligibility criteria carefully and attempt to reduce restrictive criteria. Reducing restrictive eligibility criteria will allow more patients to be eligible for clinical trial participation, will likely increase the speed of drug approvals, and will result in clinical trial results that more accurately reflect treatment of the population in the clinical setting.

e13027 Background: Despite the ubiquitous prescribing of pain medications (PMs) in cancer clinical trials, the impact of such prescribing patterns and reporting on the experience of pain is not often investigated. We examined patient-reported pain before initiation of PM reporting and at the next available pain assessment. Our aim was to understand change in patient-reported pain. Methods: We pooled data from 7 phase 3 randomized, controlled, registration trials of CDKI with endocrine therapy in patients with hormone receptor positive, human epidermal growth factor receptor-2 negative MBC. We restricted our analyses to patients who started therapy with no PM reported and looked at patients who had NSAID or opioid medication documented. We calculated change between 2 assessments in patient-reported pain before and after PM using the pain occurrence item (Q9) on the EORTC Quality of Life questionnaire (QLQ-C30). Results: Of the 4200 patients who received at least 1 dose of CDKI/placebo, 1488 started with no documented PM, with 48% reporting none at all when asked about pain at baseline. Subsequently, 185 patients had documented NSAID and 43 an opioid and had a pain PRO assessment before and after. NSAIDs documentation occurred on average 11 weeks into trial and opioids 5. Before documentation of NSAIDs, 45% of patients reported no pain compared to 23% of patients with an opioid. Patients who had documented NSAIDs, 29% experienced an improvement in their self-reported pain, whereas 32% of patients with documented opioids improved. On average the time between the 2 pain assessments was around 58 days for both PMs. Conclusions: In this analysis in patients who had a pain assessment before and after documentation of a PM, there is a small group whose pain improved. It is important to note that patients’ response to the pain item was not provided to the clinical care team, which may explain why there may have been suboptimal pain control. Further study is needed to examine how pain management can be achieved in patients with advanced breast cancer. Future analysis should be performed with patients whose PRO pain results are communicated with the clinical care team in real-time. [Table: see text]

e24145 Background: Pain medications (PMs) are commonly used to treat pain in patients (pts) with advanced/metastatic breast cancer (MBC). We examined PM usage patterns in pts receiving CDK 4/6 inhibitor (CDKI) based treatment. Methods: We pooled data from seven phase 3 randomized, controlled trials of CDKI + endocrine therapy in pts with hormone receptor positive, human epidermal growth factor receptor-2 negative MBC. PM were categorized as opioid (includes codeine-containing), NSAID, or other (i.e. bone-directed, antiepileptic, topical PMs). All analyzed pts received at least 1 dose of CDKI/placebo and had concomitant PM with a documented start date. Medications prescribed during hospitalizations were not included. We evaluated percent PM by demographic factors and pts with bone mets, and liver/lung mets. Results: 2416 pts met the inclusion criteria, of which 928 pts started a PM before the study and 1488 pts did not start PM before the study. Of the 1488 pts not on a PM before the study, 739 started a PM after study started, and 749 did not receive any PM at any time. Of the 739 pts who started a PM only after study start, overall, 59% were prescribed only an NSAID, 10% were prescribed only opioid, 17% were prescribed both an NSAID and opioid, and 14% were prescribed other PMs. The PM use by percent in demographic subgroups in the 1488 pts who took none or more PMs only after study start are presented in the table. Conclusions: To our knowledge, this is the first analysis of PM usage patterns in pts with MBC receiving CDKI or placebo with hormonal therapy on clinical trials. NSAID use was higher than opiates in all prespecified subgroups. Future analyses will examine the benefit of different classes of pain medications in treating symptoms of pain and whether there are differences between study treatment arms Percent PM Use by Class (Patients Who Took None or More PM Only After Study Start). [Table: see text]

The FDA approved niraparib, a poly(ADP-ribose) polymerase (PARP) inhibitor, on March 27, 2017, for maintenance treatment of patients with recurrent epithelial ovarian, fallopian tube, or primary peritoneal cancer who are in response to platinum-based chemotherapy. Approval was based on data from the NOVA trial comparing niraparib with placebo in two independent cohorts, based on germline BRCA mutation status (gBRCAm vs. non-gBRCAm). Progression-free survival (PFS) in each cohort was the primary endpoint. In the gBRCAm cohort, estimated median PFS on niraparib was 21 months versus 5.5 months on placebo [HR, 0.26; 95% confidence interval (CI), 0.17–0.41; P < 0.0001]. In the non-gBRCAm cohort, estimated median PFS for niraparib and placebo was 9.3 and 3.9 months, respectively (HR, 0.45; 95% CI, 0.34–0.61; P < 0.0001). Common adverse reactions (>20% and higher incidence in the niraparib arm) with niraparib included thrombocytopenia, anemia, neutropenia, nausea, constipation, vomiting, mucositis, fatigue, decreased appetite, headache, insomnia, nasopharyngitis, dyspnea, rash, and hypertension. There were five cases of myelodysplastic syndrome and acute myeloid leukemia (1.4%) in patients treated with niraparib compared with two cases (1.1%) on placebo. Niraparib is the first PARP inhibitor approved as maintenance therapy for patients with ovarian, fallopian tube, or primary peritoneal cancer, with improvement in PFS, regardless of gBRCAm status. Clin Cancer Res; 24(17); 4066–71. ©2018 AACR. See related commentary by Konstantinopoulos and Matulonis, p. 4062

Specific patient populations are often excluded from oncology trials without clear reasons, which renders results less clearly applicable to all patients. A more logical approach would be to study safety in a broad population and modify criteria as knowledge emerges.

LBA108 Background: Restrictive trial eligibility criteria limit data generalizability and patient opportunity to participate. We compared numbers and characteristics of patients (pts) eligible using traditional vs expanded criteria recommended by ASCO and Friends of Cancer Research. Methods: A retrospective, observational analysis used deidentified EHR data from ASCO’s CancerLinQ database. Study cohort included adult aNSCLC pts with ≥2 visits and ≥1 dose of systemic treatment post-advanced-disease diagnosis from 2011-2018. Recorded creatinine clearance (CrCl) or Cockcroft-Gault variables were required. Pts were grouped by traditional criteria (no brain metastases, no other malignancies and CrCl >60 mL/min) and expanded criteria (brain metastases and other malignancies allowed and CrCl >30 mL/min). Results: 10,500 pts were identified (Table). Median age 67.6 years [IQR 60.3-74.4]. 56% were male, and 65% white. 60% were Stage IV, 80% former or current smokers. 5005 (47.7%) pts were excluded by traditional exclusion criteria, while only 154 (1.5%) pts were excluded by expanded criteria. Expanded criteria patients were older (67.5 v 66.1, p

4556 Background: Registrational trials of PD-1/PD-L1 inhibitor therapy help inform clinicians and patients about the expected outcomes of patients receiving these drugs. However, the clinical trial population does not reflect all patients with the underlying disease. There have been ongoing efforts to expand eligibility criteria for clinical trial enrollment that are expected to mitigate some of these factors. We reviewed four registrational trials of PD-1/PD-L1 inhibitor therapy to better understand why patients were deemed ineligible for trial enrollment and whether expanded eligibility criteria may have addressed the reasons for ineligibility. Methods: We reviewed four trials that led to approval of PD-1/PD-L1 inhibitor therapy. These trials screened 1931 and enrolled 1253 patients with metastatic or locally advanced urothelial cancer who had previously received platinum-based therapy. We examined the datasets to determine patient demographics and reasons for trial ineligibility. Results: There were no differences in the demographics characteristics of patients who were eligible or ineligible for study treatment. However, when compared to the SEER database the screened population was younger, and minorities were under-represented. Causes of patient ineligibility included: 1) Lack of Tumor Tissue/PD-L1 Low Tumor Staining (23%), 2) Underlying Disease characteristics were not met (19%), 3) Laboratory Abnormalities (18%), 4) Excluded Co-morbid Conditions (16%), 5) Poor Performance Status (15%), 6) Refused Consent (10%), 7) Other (7%), and 8) Incorrect Prior Therapy (5%). Conclusions: Clinical trial accrual should be representative of all patients with the underlying disease. Changes in trial eligibility criteria such as less stringent requirements concerning tumor tissue (when possible), co-morbid conditions, laboratory abnormalities, and performance status may improve patient accrual. These, when added together, formed the majority of the reasons for clinical trial ineligibility.

On December 11, 2015, the FDA approved uridine triacetate (VISTOGARD; Wellstat Therapeutics Corporation) for the emergency treatment of adult and pediatric patients following a fluorouracil or capecitabine overdose regardless of the presence of symptoms, and of those who exhibit early-onset, severe, or life-threatening toxicity affecting the cardiac or central nervous system, and/or early onset, unusually severe adverse reactions (e.g., gastrointestinal toxicity and/or neutropenia) within 96 hours following the end of fluorouracil or capecitabine administration. Uridine triacetate is not recommended for the nonemergent treatment of adverse reactions associated with fluorouracil or capecitabine because it may diminish the efficacy of these drugs, and the safety and efficacy of uridine triacetate initiated more than 96 hours following the end of administration of these drugs has not been established. The approval is based on data from two single-arm, open-label, expanded-access trials in 135 patients receiving uridine triacetate (10 g or 6.2 g/m2 orally every 6 hours for 20 doses) for fluorouracil or capecitabine overdose, or who exhibited severe or life-threatening toxicities within 96 hours following the end of fluorouracil or capecitabine administration. Ninety-six percent of patients met the major efficacy outcome measure, which was survival at 30 days or survival until the resumption of chemotherapy, if prior to 30 days. The most common adverse reactions were vomiting, nausea, and diarrhea. This article summarizes the FDA review of this New Drug Application, the data supporting approval of uridine triacetate, and the unique regulatory situations encountered by this approval. Clin Cancer Res; 22(18); 4545–49. ©2016 AACR.

Poly (ADP-ribose) polymerases (PARPs) are a family of enzymes involved in cellular homeostasis, including DNA transcription, cell-cycle regulation, and DNA repair (1, 2). PARPs can detect DNA damage and bind to DNA single strand breaks (SSBs) through their N-terminal zinc finger domains. DNA binding activates the C-terminal catalytic domain, which hydrolyzes NAD+ to attach poly ADP-ribose (PAR) polymers covalently to nuclear proteins, including PARP itself. Negatively charged PAR polymers promote recruitment of DNA repair proteins, and auto-PARylation causes dissociation of PARPs from DNA, allowing completion of DNA repair. In the absence of PARP activity, unrepaired SSBs can lead to more deleterious double strand breaks (DSBs), which require high fidelity, homologous recombination (HR) or low fidelity, non-homologous end joining (NHEJ) for repair. In vitro and in vivo studies have demonstrated that tumor cells harboring defects in DNA repair are highly sensitive to PARP inhibitors, leading to genomic instability and cell death. Two publications demonstrated the concept of synthetic lethality in BRCA-deficient cells treated with PARP inhibitors (3, 4). Cells lacking functional alleles of BRCA are defective in HR repair and have an increased susceptibility to cause tumor development. Loss of BRCA or inhibition of PARP alone has little effect on in vitro and in vivo tumor growth; however, loss of function of both proteins enhances anti-tumor activity. Restoring BRCA expression blocks the cytotoxic effects of PARP inhibitor treatment. Several clinical PARP inhibitors are under investigation in Phase 2 and Phase 3 clinical trials as monotherapy in cancers with DNA repair defects or in combination with radiation, chemotherapy, or other targeted agents (Table ​(Table1).1). Progress in PARP inhibitor development has led to the recent accelerated approval of Lynparza (olaparib) by the U.S. Food and Drug Administration (5). Lynparza is currently indicated as monotherapy for patients with advanced germline BRCA-mutated ovarian cancer who have received three or more prior lines of chemotherapy. Lynparza was approved with a companion diagnostic test to select patients with deleterious or suspected deleterious BRCA mutations. PARP inhibitors are anticipated to have a much broader clinical application in additional tumor types, particularly those with DNA repair defects and in combination with chemotherapy and other targeted agents. In light of renewed interest in PARP inhibitors and the recent approval of Lynparza, this review will highlight data of PARP inhibitors in in vitro and in vivo cancer models and explore some of the clinical applications and challenges of PARP inhibitor therapy. Table 1 PARP inhibitors in Phase 2 and Phase 3 clinical developmenta. Mechanisms of Anti-Tumor Effect of Parp Inhibitors Poly (ADP-ribose) polymerase inhibitors are structurally similar in that they contain a nicotinamide moiety and mimic the NAD+ substrate. PARP inhibitors competitively bind to the catalytic domain of PARPs and inhibit PAR synthesis with half-maximal inhibitory concentration (IC50) values in the low nanomolar range (6–8). PARP inhibitors were developed to block the enzymatic activity of PARPs and prevent SSB repair by inhibiting the base excision repair (BER) pathway, and initial clinical development focused on potentiating the effects of chemotherapy and radiation (6, 9, 10). Subsequent studies demonstrated that PARP inhibitors alone were cytotoxic in HR-deficient cells (3, 4, 11). Based on these findings, a model was proposed in which PARP inhibition causes unrepaired SSBs, which are subsequently converted to DSBs, leading to synthetic lethality in HR-deficient cells (4). However, knockdown of XRCC1, the protein immediately downstream of PARP in the BER pathway did not lead to synthetic lethality (12), suggesting that loss of PARP activity is critical for synthetic lethality, but the loss of BER is not. Poly (ADP-ribose) polymerases function in other aspects of DNA repair, and emerging data suggest other mechanisms of action for the anti-tumor activity of PARP inhibitors in HR-deficient cells (13, 14). One potential mechanism proposes that PARP inhibition activates NHEJ in HR-deficient cells, leading to genomic instability and cell death (12). In vitro studies have demonstrated that PARPs can regulate components of the NHEJ machinery, including DNA-dependent protein kinase (DNA-PK), Ku70, and Ku80 (15–18). In HR-deficient cells, PARP inhibitor treatment induced the activation of DNA-PK and phosphorylation of downstream substrates and increased NHEJ of a reporter plasmid containing a DSB (12). Pharmacological blockade or loss of NHEJ proteins reduced chromosomal aberrations and the cytotoxic effects of PARP inhibition, indicating a role for NHEJ in PARP inhibitor activity. In vitro studies have demonstrated that the activity of PARP inhibitors may also involve formation of deleterious PARP–DNA complexes, which hinder DNA replication and repair (19–21). Avian cells lacking PARP1 and PARP2 were resistant to olaparib treatment and remained viable at concentrations greater than 10 μM (19). In contrast, olaparib caused significant cytotoxicity in wild type cells and increased levels of γ-H2AX, a marker of DNA damage. PAR polymers were undetectable by ELISA in both olaparib-treated wild type cells and PARP-deficient cells, suggesting that PARP inhibition is distinct from genetic deletion of PARP. A comparison of PARP inhibitors demonstrated comparable inhibition of PAR synthesis by Western blot and ELISA (19, 20). In contrast, each PARP inhibitor showed varying ability to induce PARP–DNA complexes in the presence of alkylating agent. In the absence of PARP inhibitor, PARP1 was detected in the nuclear soluble fraction by Western blot and accumulated in the chromatin-bound fraction following PARP inhibitor treatment. In tumor cells, BMN 673 (talazoparib) induced greater accumulation of PARP1 and PARP2 in the chromatin-bound fraction compared to olaparib and rucaparib. Niraparib induced greater PARP–DNA binding than olaparib, and veliparib was the least effective enhancer of PARP–DNA binding at concentrations that maximally inhibited PARP enzymatic activity. PARP–DNA binding was detected at pharmacologically relevant concentrations and correlated with the cytotoxicity of each agent in vitro. In vivo, enhanced PARP–DNA binding did not correlate with better anti-tumor activity but resulted in increased toxicity (22). The significance of differential PARP–DNA binding on efficacy and tolerability requires further investigation in the context of different tumor types and different PARP inhibitor and chemotherapy regimens. The complex role of PARPs in cellular homeostasis, including DNA repair, highlights the need to evaluate PARP inhibitors for modulating other biological functions of PARPs.

On December 19, 2014, the FDA approved olaparib capsules (Lynparza; AstraZeneca) for the treatment of patients with deleterious or suspected deleterious germline BRCA-mutated (gBRCAm) advanced ovarian cancer who have been treated with three or more prior lines of chemotherapy. The BRACAnalysis CDx (Myriad Genetic Laboratories, Inc.) was approved concurrently. An international multicenter, single-arm trial enrolled 137 patients with measurable gBRCAm-associated ovarian cancer treated with three or more prior lines of chemotherapy. Patients received olaparib at a dose of 400 mg by mouth twice daily until disease progression or unacceptable toxicity. The objective response rate (ORR) was 34% with median response duration of 7.9 months in this cohort. The most common adverse reactions (≥20%) in patients treated with olaparib were anemia, nausea, fatigue (including asthenia), vomiting, diarrhea, dysgeusia, dyspepsia, headache, decreased appetite, nasopharyngitis/pharyngitis/upper respiratory infection, cough, arthralgia/musculoskeletal pain, myalgia, back pain, dermatitis/rash, and abdominal pain/discomfort. Myelodysplatic syndrome and/or acute myeloid leukemia occurred in 2% of the patients enrolled on this trial. Clin Cancer Res; 21(19); 4257–61. ©2015 AACR.