Azacitidine (Onureg)

CADTH recommends that Onureg be reimbursed by public drug plans as maintenance therapy for the treatment of adult patients with acute myeloid leukemia (AML) who have achieved complete remission (CR) or complete remission with incomplete blood count recovery (CRi) after induction therapy with or without consolidation treatment, and are ineligible for hematopoietic stem cell transplantation (HSCT), if certain conditions are met. Onureg should only be covered to treat adult patients (at least 18 years of age) with newly diagnosed AML who have certain genetic changes that lead to greater risk of having unfavourable disease outcomes (i.e., intermediate- or poor-risk cytogenetics) and who are ineligible for HSCT. Patients eligible for reimbursement of Onureg must have achieved first remission (defined as CR or CRi) following induction with or without consolidation chemotherapy, have an Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 3, and adequate organ function. Onureg should only be reimbursed if prescribed by clinicians with expertise managing patients with AML, familiarity with Onureg’s toxicity profile exists, and its cost is reduced.

Encorafenib (Braftovi)

CADTH recommends that Braftovi should be reimbursed by public drug plans for the treatment of metastatic colorectal cancer (mCRC) if certain conditions are met. Braftovi should only be reimbursed when given in combination with cetuximab, prescribed by clinicians with experience in treating colorectal cancer, and the cost of Braftovi is reduced. Braftovi should only be covered for patients who have BRAF V600E–mutated mCRC, have received at least 1 previous systemic treatment for mCRC, have good performance status, and have adequate organ function. Braftovi should not be reimbursed for patients who have had previous treatment with epidermal growth factor receptor (EGFR) inhibitors or BRAF inhibitors.

How do we sequence therapy for marginal zone lymphomas?

Marginal zone lymphomas are indolent diseases. Overall survival rates are very good, but patients tend to relapse and may do so several times. The concept of treatment sequencing is therefore important and necessary to preserve adequate organ function and to avoid excessive toxicity, with the final goal of achieving long survival times. Systemic treatments and chemotherapy are considered to be an option in multiply relapsing disease, in cases that are in an advanced stage at presentation or relapse, and in cases where initial local treatments lack efficacy. Targeted agents and new drugs can provide chemotherapy-free alternatives in heavily pretreated patients.

A Phase I Study of OMN54 (Aneustat™) in Patients with Advanced Malignancies

Background/Objective: With the increasing interest in natural products, a phase I openlabel study of OMN54 (Aneustat™) in patients with advanced malignancies was initiated to determine toxicity, maximum tolerated dose (MTD), dose limiting toxicities (DLT), and pharmacokinetics (PK). OMN54 is a multitargeted agent, combining three Chinese botanicals; Ganoderma lucidium, Salvia miltiorrhiza and Scutellaria barbata. Methods: Eligible patients (pts) were >18 years of age with advanced solid tumors, able to swallow oral capsules, ECOG performance status < 2, measurable disease as defined by RECIST 1.1 and adequate organ function. Results: Twenty-two patients were enrolled in 6 dose levels, 2 with daily dosing and 4 with twicedaily dosing ranging from 1 to 5 grams daily. All were evaluated for toxicity and 20 for response. No treatment-related dose-limiting toxicities (DLTs) were reported and the recommended phase II dose (RP2D) was determined to be 2.5 g twice daily. Seven adverse events in 5 patients were reported as possibly drug-related; 6 were GI toxicity and 1 was a skin disorder. All were grade 1 except one grade 2 vomiting. No RECIST responses were seen. Six pts were treated with > 2 cycles; one for 8 cycles. Four patients had reductions in TGF –β and EGF, exploratory biomarkers possibly suggestive of a drug effect. Plasma half-lives of 1 -2 hours were noted for all parent drug chemical markers with no accumulation over time. Conclusion: OMN54 was well tolerated, with no DLTs observed. Further studies at the RP2D will assess the biological activity.

Phase I Alexander study of AUTO3, the first CD19/22 dual targeting CAR T cell therapy, with pembrolizumab in patients with relapsed/refractory (r/r) DLBCL.

8001 Background: CD19 directed CAR T cells are effective in patients with r/r DLBCL, however relapses due to CD19 loss or PDL1 upregulation are common. In this study, we evaluate the safety and efficacy of AUTO3, a CAR T targeting CD19/22 with limited duration of PD-1 blockade. Methods: We constructed a bicistronic retroviral vector encoding both an anti-CD19 (OX40 co-stim) and an anti-CD22 (41BB co-stim) CAR with humanized binders. The cell product was manufactured in a semi-automated and closed process using CliniMACS Prodigy. Patients (≥ 18 years) with r/r DLBCL (NOS) or transformed (tDLBCL); ECOG <2, adequate organ function are eligible. Lymphodepletion was Flu/Cy prior to AUTO3. Bridging therapy was allowed. The three dose levels explored are 50, 150, and 450 x 10^6 CAR T cells. Patients received AUTO3 alone, or with 3 doses of pembrolizumab (pem) 200 mg q 3 wks starting on D14 (regimen A), or with a single dose of pem 200 mg on D-1 (regimen B). The primary endpoint is frequency of DLTs and grade (G) 3-5 adverse events (AE) and secondary endpoints included ORR, CRR, and biomarkers. Results: As of Jan 21, 2020, 28 patients underwent leukapheresis, 27 successfully manufactured, 1 being manufactured, and 19 patients treated with AUTO3. The median age was 57 (28 - 71) and median number of prior therapies was 3 (2 - 10). 89% had refractory disease, 74% were DLBCL NOS, and 26% were tDLBCL. Dose escalation from 50 to 450 x 106 cells with pem regimen A and B have been completed without DLTs. G > 3 treatment emergent AEs that occurred > 15% were neutropenia (89%), thrombocytopenia (58%), anemia (47%), febrile neutropenia (16%), and hypophosphataemia (16%). Across all dose levels, there were 0% sCRS with primary infusion and 5% severe neurotoxicity (sNT) (1/19), which resolved. There were no cases of sCRS and no neurotoxicity of any grade at > 50 x 106 cells. Eighteen patients were evaluable for efficacy. Among the 11 treated at dose > 50 x 106, the ORR and CRR were 64% and 55%, and all CRs are ongoing (1-12 mth). Two out of 3 patients achieved CR at 450 x 106 cells on pem regimen B. Additional patients and longer follow up, as well as biomarkers, will be presented. Conclusions: AUTO3 at > 50 x 106 CAR T cells with pembrolizumab induces CRs without severe CRS or neurotoxicities of any grade. Clinical trial information: NCT03287817 .

Phase I study to assess the safety, tolerability, pharmacokinetics/pharmacodynamics and preliminary efficacy of SC10914 in patients with advanced solid tumors.

6047 Background: SC10914 is a highly selective inhibitor of PARP enzymes, including PARP1 and PARP2. SC10914 has a similar structure with olaparib. We conducted a phase I study to assess the safety, tolerability, PK/PD and preliminary efficacy of SC10914 in patients with advanced solid tumors. Methods: This is a phase I dose-escalation study with 3+3 design, we enrolled patients at 4 sites in China. Eligible patients were diagnosed with advanced solid malignancies who are refractory to standard therapies or for which no standard therapy exists; had measurable disease; had adequate organ function. Patients received SC10914 daily at ten escalating doses from 30 mg QD to 500 mg TID in a 28-day cycle. We obtained blood for PK and CA125 assessments. Toxic effects were assessed by CTCAE 4.03 criteria and tumour responses ascribed by RECIST 1.1 and CA125 was assessed by GCIG criteria. Results: As of January 2020, 52 patients were enrolled, of which 14 were males and 38 were females. Ten doses were escalated to 500mg TID, and no DLT was observed, and MTD was not obtained. The incidence of grade 3/4 AEs and SAEs that were related to SC10914 were 34.6% (18/52) and 13.5% (7/52). Grade 3/4 adverse reaction happened in at least two patients were anaemia/reduced hemoglobin (10/52, 19.2%), decreased WBC count (5/52, 9.6%), neutropenia (3/52, 5.8%), thrombocytopenia (2/52, 3.8%), and decreased lymphocyte count (2/52, 3.8%). A total of 17 gBRCAm evaluable ovarian cancer patients were enrolled, 6 of them had PR, the ORR was 35.3% (6/17). 10 gBRCAm ovarian cancer patients were enrolled in TID groups (including 2 patients who received BID doses at the beginning and changed to 300 mg TID dose after several cycles of treatment), 5 of them had PR, the ORR was 50% (5/10). The ORR of 400 mg TID group was 66.7%(4/6). PK data showed that the exposure of SC10914 was increased with dose increasing at the dose of 30 mg to 250 mg. The half-life of SC10914 was about 2-5 hours. Conclusions: SC10914 was safe in patients with advanced solid tumors. The main toxicity was blood-related adverse reactions. SC10914 was effective in gBRCAm ovarian cancer patients. 400 mg TID might be RP2D. Clinical trial information: NCT02940132.

A randomized phase II trial comparing switch to nivolumab with TKI continuation after 12 weeks of TKI induction therapy in metastatic renal cell carcinoma patients (NIVOSWITCH).

678 Background: Tyrosine kinase inhibitors (TKI) and Nivolumab (NIVO) are standard treatment options for mRCC. We tested whether TKI followed by early switch to NIVO improved outcome in mRCC patients (pts). Methods: Main inclusion criteria: measurable advanced or metastatic clear cell RCC, ECOG PS 0-2, adequate organ function, PR or SD to induction therapy with sunitinib (50 mg, 4-2 regime) or pazopanib (800 mg OD). 1:1 randomization at 12 wks.: TKI continuation vs. switch to NIVO (240 or 480 mg IV q2-4wks). Strata were MSKCC risk, TKI used and response to TKI. Imaging was performed q12w. 49 of 244 planned pts were randomized between Dec 2016 and Aug 2018, which led to premature closure of the trial. We report the second interim analysis with data base lock on 31.07.19. ORR was assessed according to RECIST 1.1. Efficacy and safety analyses were performed in ITT and safety population, respectively. Log-Rank analyses were used for survival analyses. Results: 25 and 24 pts received NIVO or TKI, respectively. Median age was 65 y (range: 35-79), 82% were male and 4% had ECOG PS 2. Metastases occurred predominantly in lung (47%), lymph nodes (27%) and liver (24%). MSKCC risks were: favorable (31%), intermediate (65%), and poor (4%), which were balanced between arms. 55% received sunitinib. ORR for NIVO vs. TKI differed when assessed from start of induction therapy (64 vs. 70%, P=0.76) or from time of randomization (16 vs. 48%; P=0.032). Accordingly, PFS from randomization was 3.0 vs. 11.9 mo. (HR = 1.72 [95% CI: 1.19 – 2.48]; P=0.0026) in favor of TKI continuation. At a median follow-up of 12.9 mo. median OS was not reached, but HR = 1.86 (95% CI: 0.85 – 4.07) P=0.10 showed a trend for TKI continuation. All grades AE for NIVO vs. TKI occurred in 96% vs. 100%, grade 3-5 48% vs. 71% and serious AE 40% vs. 46%. Conclusions: In TKI-sensitive pts, continuation of TKI is more efficacious than early switch to NIVO. The major limitation of our trial is the premature closure and its limited sample size. Clinical trial information: NCT02959554.

Dose-escalation results of a phase I study of 225Ac-J591 for progressive metastatic castration resistant prostate cancer (mCRPC).

114 Background: Prostate-specific membrane antigen (PSMA) can be targeted by antibodies (Ab) or small molecule ligands labeled with potent α emitters (e.g. 225Ac). Unlike ligands, Ab biodistribution does not include non-tumor organs such as the salivary glands, kidneys and small bowel. We performed a phase I single ascending dose Ab study. Methods: Eligibility: progressive mCRPC following at least 1 potent AR pathway inhibitor (ARPI; e.g. abi/enza) and docetaxel (or unfit/refuse chemo) without limit of # prior therapies provided adequate organ function. Baseline 68Ga-PSMA11 PET was performed but not used for eligibility. Single-subject cohorts received a single infusion of 225Ac-J591 until grade (Gr) > 1 attributable toxicity or dose level 5, then transition to 3+3 design. Cohort 1 = 13.3 KBq/kg with planned escalation up to dose level 7 (93.3 KBq/kg). Dose-limiting toxicity (DLT) defined as attributable Gr 4 heme or Gr 3/4 non-heme toxicity. Results: 22 men were treated on 7 dose levels; median age 72.5 (range 58-89), PSA 146.5 (4.8-7168.4); 82% with >2 prior ARPI, 64% chemo, 45% sipuleucel-T, 23% radium-223, 55% prior 177Lu-PSMA. By standard imaging 82% bone, 36% lymph node, 9% liver mets. At the time of data cutoff, 1 of 6 men in cohort 6 (80 KBq/kg) had DLT (Gr 4 anemia and platelets); he had 4 prior cycles of 177Lu-PSMA. No other attributable Gr >2 non-hematologic or Gr >3 heme AE (including 0 of 6 at the highest dose level). Low Gr temporary AE’s include: 16 (73%) with fatigue, 11 (50%) pain, 11 (50%) nausea, 6 (27%) with xerostomia (5 of 6 with prior 177Lu-PSMA), 3 (14%) AST elevation. With follow-up ongoing, 60% with any PSA decline, 35% with >50% PSA decline. Of 10 with detectable baseline and 12-week CTC counts (CellSearch), 8 declined (45-100% decline); 5 (50%) with CTC count conversion. While PSMA uptake was not a prerequisite for treatment, all had some PSMA uptake on 68Ga-PSMA11 PET/CT; 64% with SUVmax >5x liver SUV, 14% 2.5x – 5x liver, and 23% with SUVmax 0-2.5x liver SUV. Conclusions: PSMA-targeted alpha-emitter 225Ac utilizing intact Ab J591 is well tolerated with early evidence of clinical activity in a pre-treated population, including the majority with prior 177Lu-PSMA. Clinical trial information: NCT03276572.

RESILIENT: Study of irinotecan liposome injection (nal-IRI) in patients with small cell lung cancer—Preliminary findings from part 1 dose-defining phase.

8562 Background: Nal-IRI is investigated as monotherapy in patients with SCLC who progressed on or after platinum regimen. The RESILIENT study is a Part 1 study of a Phase 2/3 trial to assess safety, tolerability, and efficacy of Irinotecan Liposome Injection in patients with SCLC. Methods: Nal-IRI is evaluated in patients ≥18 yrs with advanced SCLC with an ECOG performance status ≤1 and adequate organ function; prior exposure to immunotherapy is allowed. Safety and tolerability at dose levels of 85 mg/m2 and 70 mg/m2 are the primary endpoints, with assessment of exploratory efficacy signal. Results: At 24 Dec 2018 safety cutoff 12 patients in Part 1 received ≥1 dose of nal-IRI (Cohort 1 [C-1] at 85 mg/m2 dose n=4; Cohort 2 [C-2] at 70 mg/m2 dose n=8; median age 60.0 yrs; range 49–73 yrs). Three patients experienced ≥1 DLT (Cohort 1 n=3/4; Cohort 2 n=0/8). Most frequent treatment-emergent adverse events (TEAE) were gastrointestinal (GI) disorders (any grade): diarrhea (91.7%), nausea (58.3%), vomiting (41.7%), decreased appetite (58%), abdominal pain (33%) manageable by antidiarrheal regimen and antiemetics; as well as fatigue (50%) and asthenia (37.5%). Overall, hematologic toxicity was neutropenia (any grade) at 16.7% and anemia (any grade) at 16.7%. At 11 Dec 2018 efficacy cutoff the best objective response was partial response (PR) at 33.3% in 4/12 patients (C-1 n=1/4; C-2 n=3/8), median time to response was 6 wks. Overall disease control rate (DCR) was 58.3%; progressive disease (PD) was observed in 2 patients (16.7%), and 3 patients were non-evaluable (25%). Conclusions: Initial assessment suggests that nal-IRI at 70 mg/m2 dose given bi-weekly is well-tolerated and has promising antitumor activity in patients with SCLC who progressed on or after platinum regimen. Part 1 dose expansion is ongoing. Clinical trial information: NCTN03088813. [Table: see text]

A phase I dose escalation (DE) study of ERK inhibitor, LY3214996, in advanced (adv) cancer (CA) patients (pts).

3001 Background: LY3214996 is a selective and potent ERK1/2 inhibitor that has demonstrated tumor growth inhibition in several pre-clinical tumor models with BRAF, RAS, or MAP2K1 mutations. This is the first-in-human Phase 1 Study of LY3214996 in adv CA pts. Methods: The goals of this DE study were to determine a recommended Phase 2 dose (RP2D), safety, pharmacokinetic (PK), and preliminary efficacy of LY3214996 (NCT02857270; I8S-MC-JUAB; Eli Lilly & Co.). Pts with adv CA, ≥18 yrs of age, ECOG ≤1, and with adequate organ function were eligible. Pharmacodynamic (PD) biomarkers including pRSK were evaluated in blood and paired tumor tissue. The DE phase evaluated PO doses using the Bayesian model-based toxicity band method. Results: A total of 51 pts with median age of 62 yrs (range: 21-81) received at least 1 dose of LY3214996 with a median of 3 cycles (range: 1-12). Most pts had a mutation in RAS (N = 33) or BRAF (N = 16) and had a median of 4 prior lines of treatment. The DLTs observed in the study include grade (G) 3 cough and fatigue, G3 dehydration, increased creatinine (Cr), G3 increased CPK, G3 rash > 7 days, and 1 pt with renal failure. TRAEs to LY3214996 occurring in ≥10% of pts included nausea, vomiting, diarrhea, dermatitis acneiform, fatigue, pruritus, and blurred vision. LY3214996 exposures increased with dose. Tumor regression was observed in 7 pts with BRAF/non -BRAF mutant CA including 5 pts who failed prior IO/MAPK inhibitors. Four pts achieved stable disease (2 BRAF, 1 RAS and 1 CRAF mutation) that lasted > 4 mos. Up to 100% pRSK decrease from baseline in tumor was observed. Conclusions: LY3214996 had an acceptable safety profile, favorable PK, and potent tumor PD inhibition at RP2D. This supports further exploration of LY3214996 as monotherapy and in combination in CA pts with activating MAPK pathway alterations. Clinical trial information: NCT02857270.