PIONEER-Panc: a platform trial for phase II randomized investigations of new and emerging therapies for localized pancreatic cancer

Background Personalized and effective treatments for pancreatic ductal adenocarcinoma (PDAC) continue to remain elusive. Novel clinical trial designs that enable continual and rapid evaluation of novel therapeutics are needed. Here, we describe a platform clinical trial to address this unmet need. Methods This is a phase II study using a Bayesian platform design to evaluate multiple experimental arms against a control arm in patients with PDAC. We first separate patients into three clinical stage groups of localized PDAC (resectable, borderline resectable, and locally advanced disease), and further divide each stage group based on treatment history (treatment naïve or previously treated). The clinical stage and treatment history therefore define 6 different cohorts, and each cohort has one control arm but may have one or more experimental arms running simultaneously. Within each cohort, adaptive randomization rules are applied and patients will be randomized to either an experimental arm or the control arm accordingly. The experimental arm(s) of each cohort are only compared to the applicable cohort specific control arm. Experimental arms may be added independently to one or more cohorts during the study. Multiple correlative studies for tissue, blood, and imaging are also incorporated. Discussion To date, PDAC has been treated as a single disease, despite knowledge that there is substantial heterogeneity in disease presentation and biology. It is recognized that the current approach of single arm phase II trials and traditional phase III randomized studies are not well-suited for more personalized treatment strategies in PDAC. The PIONEER Panc platform clinical trial is designed to overcome these challenges and help advance our treatment strategies for this deadly disease. Trial registration This study is approved by the Institutional Review Board (IRB) of MD Anderson Cancer Center, IRB-approved protocol 2020-0075. The PIONEER trial is registered at the US National Institutes of Health (ClinicalTrials.gov) NCT04481204.

Immune Checkpoint Inhibitors in Mismatch Repair Proficient/Microsatellite Stable Metastatic Colorectal Cancer Patients: Insights from the AtezoTRIBE and MAYA Trials

In metastatic colorectal cancer (mCRC), remarkable advances have been achieved with immune checkpoint inhibitors (ICIs) targeting PD-1/PD-L1 and CTLA-4, only in a small subset of tumours (4–5%), harbouring a deficient mismatch repair system (dMMR)/microsatellite instability–high (MSI-H) or mutations in the catalytic subunit of polymerase epsilon (POLE). Within this framework, several combination strategies have been investigated to sensitize proficient mismatch repair (pMMR)/microsatellite stable (MSS) mCRC to ICIs, with disappointing results so far. However, at the last ESMO meeting, two phase II trials AtezoTRIBE and MAYA provided promising results in this field. In the comparative AtezoTRIBE trial, the addition of atezolizumab to FOLFOXIRI (5-fluoruracil, oxaliplatin and irinotecan) and bevacizumab led to a significant advantage in terms of progression free survival (PFS) in a population of untreated mCRC patients, not selected according to MMR/MSI status. In the single-arm MAYA trial, immune priming with temozolomide in pMMR/MSS chemo-resistant mCRC patients with silencing of O6-methylguanine-DNA methyltransferase (MGMT) allowed reporting signals of sensitivity to the subsequent therapy with nivolumab and a low dose of ipilimumab in some patients. Here, we discuss the rationale, results, criticisms and research perspectives opened by these two studies.

ML-18 High-dose chemotherapy supported by autologous stem cell transplant in relapsed and refractory primary CNS lymphoma

While whole brain radiation therapy (WBRT) has been performed as consolidation therapy in primary central nervous system lymphoma (PCNSL), high-dose chemotherapy supported by autologous stem cell transplant (HDC/ASCT) is widely investigated today as an alternative treatment strategy, given the high risk for radiation-induced neurotoxicity in WBRT. Various conditioning regimens have been investigated in phase II trials, which report non-inferiority of HDC/ASCT in efficacy and preservation of neurocognitive function in comparison with WBRT. Besides its promising efficacy, treatment-related deaths are reported in 11% in patients treated by a conditioning regimen using thiotepa, busulfan and cyclophosphamide (TBC), which raises a concern for safety. Among several conditioning regimens, analysis using registry data of Japan Society for Hematopoietic Cell Transplantation has revealed that the use of conditioning regimens containing thiotepa was a positive factor for longer PFS. According to the result of a phase I trial in Japan which investigated HDC/ASCT using thiotepa and busulfan (BuTT), thiotepa was approved by the pharmaceuticals and medical devices agency (PMDA) on March 2020. In comparison with the TBC regimen, cyclophosphamide is omitted, and the dose of thiotepa is lower (250 mg/m2, 3 days in TBC; 5 mg/kg, 2 days in BuTT) in BuTT, therefore BuTT could be less toxic in comparison with TBC, and no treatment-related deaths were observed in the phase I study in Japan. Further investigation on the efficacy and safety of BuTT in actual clinical practice is warranted. We have constituted a multi-disciplinary team in our institution in order to perform HDC/ASCT using BuTT in relapsed/refractory PCNSL. Treatment indications are as follows; 65 years old or younger, previously treated by rituximab, methotrexate, procarbazine and vincristine (R-MPV), good organ function and neurological status. Future directions along with preliminary treatment results will be discussed at the meeting.

Two Clinical Cases of Metastatic Merkel Cell Carcinoma Illustrating Avelumab Tolerability in Elderly Patients

We present two cases of primary cutaneous Merkel cell carcinoma in a 80-year and a 95-year old patient. Both patients had a wide local excision, but early recurrences occurred. Case 1 required palliative radiotherapy. He did not receive chemotherapy but case 2 did. They then proceeded to have immunotherapy with sustained responses lasting greater than 2 and 3 years. This report highlights an important new class of drug for the treatment of advanced Merkel cell carcinoma. Furthermore, our case report demonstrates that avelumab immunotherapy can be safely delivered to elderly patients, including 80- and 95-year-old patients. This report parallels the high and durable response rates to avelumab (including complete responses) that were shown in the JAVELIN phase II trials.

Advantages of multi-arm non-randomised sequentially allocated cohort designs for Phase II oncology trials

Background Efficient trial designs are required to prioritise promising drugs within Phase II trials. Adaptive designs are examples of such designs, but their efficiency is reduced if there is a delay in assessing patient responses to treatment. Methods Motivated by the WIRE trial in renal cell carcinoma (NCT03741426), we compare three trial approaches to testing multiple treatment arms: (1) single-arm trials in sequence with interim analyses; (2) a parallel multi-arm multi-stage trial and (3) the design used in WIRE, which we call the Multi-Arm Sequential Trial with Efficient Recruitment (MASTER) design. The MASTER design recruits patients to one arm at a time, pausing recruitment to an arm when it has recruited the required number for an interim analysis. We conduct a simulation study to compare how long the three different trial designs take to evaluate a number of new treatment arms. Results The parallel multi-arm multi-stage and the MASTER design are much more efficient than separate trials. The MASTER design provides extra efficiency when there is endpoint delay, or recruitment is very quick. Conclusions We recommend the MASTER design as an efficient way of testing multiple promising cancer treatments in non-comparative Phase II trials.

CTNI-36. SAFETY OF ONC201 ADMINISTERED TWO CONSECUTIVE DAYS PER WEEK IN PEDIATRIC H3 K27M-MUTANT GLIOMA PATIENTS

ONC201, an anti-cancer DRD2 antagonist and ClpP agonist, is in Phase II trials for adult H3 K27M-mutant diffuse midline gliomas. The recommended phase 2 dose (RP2D) of 625mg ONC201 once a week has been established as a biologically active dose that is well tolerated in adult and pediatric populations. Radiographic regressions with single agent ONC201 have been reported in recurrent H3 K27M-mutant glioma patients. In another study, twice/week dosing was explored in adult patients and deemed to be safe (no DLTs observed). This warranted exploration of twice/week dosing in pediatric patients and will be discussed in this presentation. This multi-arm, dose-escalation and dose-expansion trial (ONC014; NCT03416530) determined the pediatric RP2D of ONC201 administered once per week and twice per week on two consecutive days. ONC201 was orally administered and scaled by body weight. Dose escalation was performed by a 3 + 3 design beginning with two 125mg capsules less than the adult RP2D equivalent. Twelve children (8 females; 4 males) with H3 K27M-mutant gliomas (pons: 8; thalamus: 2; spinal cord: 2) aged 4-19 years have been treated post-radiation: 3 at dose level -1; 3 at dose level 1; 6 as part of the dose expansion cohort on dose level 2. Median KPS was 90 (range 70-100). One treatment cycle was 21 days (6 doses), which also defined the DLT window. Patients were on-treatment for a median length of 4 cycles (range: 2-11). Twice weekly dosing of ONC201 was tolerated well, as observed with weekly dosing, with no instance of DLT. A total of 4 SAEs were reported, none of which were related to the study drug. The most common AEs (regardless of relatedness) included headache, facial nerve disorder, abducens nerve disorder, nausea, fatigue and ataxia. Additional safety data, PK, and clinical outcomes from this arm will be reported.

411 INNATE: immunotherapy during neoadjuvant therapy for rectal cancer to elucidate local and systemic therapeutic responses

BackgroundThe relative risk of developing rectal cancer has quadrupled in young adults over the last 40 years and approximately 50% of patients develop recurrence within 3 years. Thus, there is a critical need for new approaches to improve survival but cancer Immunotherapy has had little impact on colorectal cancer. The anti-CD40 agonist immunotherapy is emerging and APX005M has shown promise in phase I and ongoing phase II trials. Anti-CD40 can stimulate both innate and adaptive immune responses and a greater response can be achieved combining anti-CD40 with radiation therapy (RT) in animal models. We developed the INNATE trial, a phase II randomized trial of neoadjuvant short course RT followed by chemotherapy with or without the addition of APX005M for rectal cancer (NCT04130854).MethodsThe INNATE trial is a multi-center, 58 patient, 3:2 randomization clinical trial, that adds APX005M to short course RT (SCRT) and subsequent FOLFOX chemotherapy prior to definitive radiation. Eligibility includes stage III and high risk stage II rectal cancer and candidates for standard neoadjuvant therapy and no contraindications for immunotherapy or radiation. Patients receive 5Gy x 5 fractions over five days and if randomized to experimental arm will receive APX005M on day 3 of radiation. After a two week break patients receive an optional endoscopy and biopsy followed by standard FOLFOX chemotherapy with APX005M infusion after disconnection of 5-FU chemotherapy pump. Study arm receives APX005M with 5 of 6 cycles of FOLFOX. After treatment patients undergo restating, endoscopy, and trans abdominal resection. The primary endpoint is pathologic complete response with the null estimated to be 20% and alternative 50% for a power of 0.8 and type 1 error of 0.1. Secondary endpoints include overall survival, toxicity analysis, and disease free survival. For correlative analysis, tissue is collected pre-treatment, two weeks after RT, and at surgery, then blood collected during treatment and at follow up.ResultsTo date 16 patients have been randomized and initiated treatment. The treatment is well tolerated. Fiveteen patients received pre- and post-SCRT biopsies. The study team plans correlative analysis including single cell RNA sequencing, multiplex imunohistochemistry, and bulk sequencing. Preliminary data shows changes in the immune tumor microenvironment from patients treated as their own control and between SCRT versus SCRT + APX00M.ConclusionsThe INNATE trial shows feasibility of incorporating novel immunotherapies with an emerging standard of care incorporating short course RT. It serves as an important platform for scientific and clinical investigation.Trial RegistrationClinicaltrialsgov: NCT04130854Ethics ApprovalThe clinical trial has institutional review board approval at the University of Texas Southwestern, Oregon Health and Sciences University, Wake Forest, and Moffitt. All patients have provided informed consent.

Molnupiravir—A Novel Oral Anti-SARS-CoV-2 Agent

Since December 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has rapidly resulted in a global pandemic with approximately 4 million deaths. Effective oral antiviral agents are urgently needed to treat coronavirus disease-2019 (COVID-19), block SARS-CoV-2 transmission, and prevent progression to severe illness. Molnupiravir (formerly EIDD-2801), a prodrug of beta-D-N4-hydroxycytidine (EIDD-1931) and an inhibitor of RNA-dependent RNA polymerase, possesses significant activity against SARS-CoV-2. Its prophylactic efficacy has been evidenced in a ferret model. Two phase-I trials (NCT04392219 and NCT04746183) have demonstrated that oral molnupiravir is safe and well-tolerated at therapeutic doses. After five-days of oral molnupiravir therapy, satisfactory efficacies, assessed by eliminating nasopharyngeal virus in patients with early and mild COVID-19, were disclosed in two phase-II trials (NCT04405739 and NCT 04405570). Two phase-II/III trials, NCT04575597 and NCT04575584, with estimated enrollments of 1850 and 304 cases, respectively, are ongoing. The NCT04575597 recently released that molnupiravir significantly reduced the risk of hospitalization or death in adults experiencing mild or moderate COVID-19. To benefit individual and public health, clinical applications of molnupiravir to promptly treat COVID-19 patients and prevent SARS-CoV-2 transmission may be expected.