Local delivery of hrBMP4 as an anticancer therapy in patients with recurrent glioblastoma: a first-in-human phase 1 dose escalation trial

BACKGROUND

This Phase 1 study evaluates the intra- and peritumoral administration by convection enhanced delivery (CED) of human recombinant Bone Morphogenetic Protein 4 (hrBMP4) - an inhibitory regulator of cancer stem cells (CSCs) - in recurrent glioblastoma.

METHODS

In a 3 + 3 dose escalation design, over four to six days, fifteen recurrent glioblastoma patients received, by CED, one of five doses of hrBMP4 ranging from 0·5 to 18 mg. Patients were followed by periodic physical, neurological, blood testing, magnetic resonance imaging (MRI) and quality of life evaluations. The primary objective of this first-in-human study was to determine the safety, dose-limiting toxicities (DLT) and maximum tolerated dose (MTD) of hrBMP4. Secondary objectives were to assess potential efficacy and systemic exposure to hrBMP4 upon intracerebral infusion.

RESULTS

Intra- and peritumoral infusion of hrBMP4 was safe and well-tolerated. We observed no serious adverse events related to this drug. Neither MTD nor DLT were reached. Three patients had increased hrBMP4 serum levels at the end of infusion, which normalized within 4 weeks, without sign of toxicity. One patient showed partial response and two patients a complete (local) tumor response, which was maintained until the most recent follow-up, 57 and 30 months post-hrBMP4. Tumor growth was inhibited in areas permeated by hrBMP4.

CONCLUSION

Local delivery of hrBMP4 in and around recurring glioblastoma is safe and well-tolerated. Three patients responded to the treatment. A complete response and long-term survival occurred in two of them. This warrants further clinical studies on this novel treatment targeting glioblastoma CSCs.

TRIAL REGISTRATION

ClinicaTrials.gov identifier: NCT02869243.

Abstract OT2-01-05: A phase 2 randomized, double-blind, placebo-controlled trial of hormone therapy ± radium-223 dichloride in human epidermal growth factor receptor 2–negative, hormone receptor–positive breast cancer patients with bone metastases

Background: Treatment options for bone-metastatic breast cancer (MBC) are limited. Multimodality therapy may improve symptom control and survival. In a phase 2a study of advanced breast cancer patients with bone-dominant and no visceral disease, radium-223 dichloride (radium-223), a first-in-class α-emitter selectively targeting bone metastases, reduced baseline bone biomarker levels with favorable safety (Coleman et al. Breast Cancer Res Treat 2014). This study (NCT02258464) evaluates efficacy and safety of radium-223 versus placebo in human epidermal growth factor receptor 2–negative (HER2-), hormone receptor–positive (HR+) bone-MBC patients receiving single-agent hormone therapy.

Trial design: Patients receive (1:1) radium-223 50 kBq/kg IV or placebo q 4 wk (6 cycles) + concurrent single-agent hormone therapy + best supportive care. Stratification is by geographic region, prior lines of hormone therapy for MBC, and number of prior skeletal events.

Main eligibility criteria: Eligible patients are pre- or postmenopausal with estrogen receptor–positive, HER2-, bone-dominant MBC with ≥ 2 bone metastases and ≥ 1 or 2 prior symptomatic skeletal events (external beam radiotherapy for bone pain, pathologic bone fracture, spinal cord compression, orthopedic surgery). Patients had ≥ 1 line of hormone therapy for MBC; are taking bisphosphonates or denosumab for ≥ 1 month before study; are eligible for endocrine treatment; and have evaluable disease (RECIST v1.1), asymptomatic or mildly symptomatic bone disease (Brief Pain Inventory), ECOG performance status 0-1, and adequate hematologic, renal, and liver function. Patients may not have had visceral or brain metastases or leptomeningeal disease, need for chemotherapy for metastases, and untreated spinal cord compression.

Specific aims: Patients are assessed for efficacy and safety, and followed to symptomatic skeletal events, radiologic progression, death, or withdrawal. Primary endpoint is symptomatic skeletal event–free survival.

Statistical methods: Assuming a 1-sided α of 0.1, power of 90%, ∼ 119 symptomatic skeletal events are required for the analysis. Time-to-event variables will be analyzed using a log-rank test, accounting for stratification. Kaplan-Meier estimates and survival curves will be given for each treatment group. Safety analyses will be descriptive.

Present and target accruals: As of May 2015, 5 patients have been screened and 3 enrolled. Target enrollment is 227 patients.

Citation Format: Coleman RE, Huang L, Petrenciuc O, Zaccarini P, Rugo HS. A phase 2 randomized, double-blind, placebo-controlled trial of hormone therapy ± radium-223 dichloride in human epidermal growth factor receptor 2–negative, hormone receptor–positive breast cancer patients with bone metastases. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr OT2-01-05.

Abstract OT2-01-11: A phase 2 randomized, double-blind, placebo-controlled trial of radium-223 dichloride with exemestane and everolimus in human epidermal growth factor receptor 2–negative, hormone receptor–positive breast cancer patients with bone metastases

Background: Radium-223 dichloride (Ra-223), a first-in-class α-emitter with a potent, targeted antitumor effect on bone metastases (mets), was well tolerated and reduced baseline bone biomarker levels in a phase 2 study in metastatic breast cancer (MBC) patients (pts) with bone-dominant disease (Coleman et al. Breast Cancer Res Treat 2014). Adding everolimus (EVE) to exemestane (EXE) significantly improved progression-free survival (PFS) versus EXE alone in human epidermal growth factor receptor 2–negative (HER2-), hormone receptor–positive (HR+) MBC pts with advanced disease. This trial will evaluate efficacy and safety of Ra-223 with EXE and EVE in pts with HER2-, HR+ breast cancer and bone mets (NCT02258451).

Trial design: Pts scheduled to receive EXE (25 mg PO once daily) and EVE (10 mg PO once daily) will be randomized 1:1 to Ra-223 (50 kBq/kg IV) or placebo × 6 cycles q4wk. EXE and EVE treatment (tx) will continue until disease progression, unacceptable toxicity, or the pt can no longer travel to the clinic to receive study medication. Stratification will be by geographic region, previous lines of hormone therapy, and presence of visceral disease. Safety and efficacy will be assessed at each 4-week clinic visit during tx. Long-term safety will be assessed until study termination (ie, pt death, pt loss to follow-up, or pt reaching required number of events).

Main eligibility criteria: Eligible pts are pre- or postmenopausal with estrogen receptor–positive and HER2- bone lesion–related asymptomatic or mildly symptomatic MBC not amenable to cure by surgery or radiotherapy, and with ≥2 bone mets visible on bone scan. Pts must have measurable disease per RECIST v1.1, ≥1 prior line of hormonal therapy in the metastatic setting, and 1-2 skeletal related events before study entry; be on bisphosphonates or denosumab for ≥1 mo before study entry; and have ECOG performance status of 0-1, adequate hematologic, renal, and liver function, and life expectancy ≥6 mo. Pts may not have prior or current need for chemotherapy in the metastatic setting, unresolved spinal cord compression, and prior or current EVE tx.

Specific aims: The primary endpoint is symptomatic skeletal event (SSE)–free survival. Secondary endpoints are overall survival, time to opiate use for cancer pain, time to pain progression, time to cytotoxic chemotherapy, radiologic PFS (rPFS), and acute and long-term safety. Exploratory endpoints include time to first on-study SSE, time to bone alkaline phosphatase (bALP) progression, bALP response at wk 12 and end of tx, bone-specific rPFS, resource utilization, biomarker assessments, and time to visceral mets onset.

Statistical methods: Assuming a one-sided α of 0.1, power of 90%, ∼160 SSEs will be required at the time of analysis. A stratified log-rank test will be used to analyze efficacy (intent-to-treat population). Safety analysis will be descriptive.

Present and target accrual: This trial is now enrolling pts. Target accrual is 311.

Citation Format: Rugo HS, Huang L, Petrenciuc O, Zaccarini P, Coleman RE. A phase 2 randomized, double-blind, placebo-controlled trial of radium-223 dichloride with exemestane and everolimus in human epidermal growth factor receptor 2–negative, hormone receptor–positive breast cancer patients with bone metastases. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr OT2-01-11.

Double-blind crossover study of acarbose in type 1 diabetic patients

The addition of acarbose to insulin treatment was evaluated in 14 Type 1 (insulin-dependent) diabetic patients assessed conventionally (blood glucose profile and HbA1c measurement) and with an artificial B-cell. Their metabolic control was poor, fasting blood glucose 10.7 +/- 0.3 (+/- SE) mmol l-1, mean daily blood glucose 9.7 +/- 0.3 mmol l-1, and HbA1c 9.6 +/- 0.2% (normal range 5.0-6.1%). They were of normal body weight (body mass index 22.5 +/- 0.3 kg m-2), and were C-peptide deficient (fasting 0.08 +/- 0.02 nmol l-1). In addition to their usual insulin therapy (46.9 +/- 3.5 U day-1 in three pre-meal injections), they received 100 mg acarbose or placebo three times a day for 6 weeks in a randomized double-blind crossover design. On the last day of either acarbose or placebo treatment, the usual insulin therapy was discontinued and an artificial B-cell was used for insulin delivery, programmed for euglycaemia. Placebo or acarbose was continued before meals. Acarbose reduced mean daily blood glucose concentrations (8.5 +/- 0.3 vs 9.7 +/- 0.3 mmol l-1, p = 0.002) and HbA1c levels (8.3 +/- 0.1 vs 9.6 +/- 0.2%, p less than 0.001). A significant reduction in insulin requirement after meals was found with the artificial B-cell, 25.1 +/- 2.5 (first treatment acarbose) and 24.1 +/- 2.9 U (first treatment placebo) with acarbose and 40.0 +/- 2.5 and 35.6 +/- 2.9 U with placebo (p less than 0.001). These results suggest that acarbose could usefully be administered to Type 1 diabetic patients to ameliorate glucose control and reduce insulin requirement.