AbbVie, a global biopharmaceutical company, announced on june 5th, safety and preliminary efficacy data from a Phase 1 study of ABT-414 – an investigational antibody drug conjugate (ADC) for epidermal growth factor receptor (EGFR) amplified, recurrent glioblastoma (GBM) – showed no dose-limiting toxicities and frequent, reversible ocular toxicities. Additionally, an estimated 30 percent (n=44) of patients treated with ABT-414 as monotherapy were progression free at six months [95% CI=17, 44] (secondary endpoint). These results, from an expansion cohort of one arm (Arm C) of a three-arm open-label study, were presented today at the 52nd Annual Meeting of the American Society of Clinical Oncology (ASCO) in Chicago.1 Amplified EGFR is the most common genetic mutation associated with malignant GBM, an aggressive brain cancer.2
As of January 7, 2016, the most common serious adverse event (>1 patient) (n=48) was seizure (8%). Additionally, Best Response Assessment in Neuro-Oncology (RANO) Criteria, an assessment of tumor response used in GBM, identified two partial responses, 18 patients with stable disease, and 24 with progressive disease for a total of 44 patients with complete data.1
“With standard of care therapy,3 patients with GBM, the most common and most aggressive form of brain cancer,4 have a median survival of 15 months after diagnosis and two-year survival is 30%.5 There remains an urgent unmet need for new treatment options for this devastating brain cancer,” said Martin van den Bent, M.D., Ph.D., head, Neuro-Oncology Unit, Erasmus MC Cancer Institute, the Netherlands, and lead investigator of the study. “These data are important as they demonstrate the potential of ABT-414 and underscore the need for further investigation in glioblastoma.”
Grade 3/4 treatment emergent adverse events (TEAEs) (>1 patient) were keratitis (15%), corneal epithelial microcysts (8%), hemiparesis (6%), hyperglycemia (6%), muscular weakness (6%), seizure (6%), blurred vision (4%) and ulcerative keratitis (4%).The most common TEAEs (≥25% patients) in this study arm were blurred vision (60%), headache (29%), photophobia (29%), dry eye (27%), eye pain (27%), and fatigue (27%). The most common serious adverse event (>1 patient) (n=48) was seizure (8%).1
“These results suggest that ABT-414 may have important activity for certain groups of patients with glioblastoma and support the continuation of the ongoing randomized studies,” said Gary Gordon, M.D., vice president, oncology clinical development, AbbVie. “AbbVie is committed to continuing to invest in technologies and approaches, including antibody drug conjugates like ABT-414, with the goal of delivering a remarkable impact on cancer treatment.”
Based on these results, together with previously presented data from this study, AbbVie advanced ABT-414 to a randomized Phase 2 clinical trial in patients with EGFR-amplified GBM.1
The Phase 1, open-label trial was designed to evaluate the safety, pharmacokinetics and maximum tolerated dose of ABT-414. Three study arms evaluated ABT-414 with radiotherapy and temozolomide (TMZ) in patients with newly diagnosed glioblastoma (GBM) (Arm A), with TMZ in patients with newly diagnosed glioblastoma who have just completed radiation and TMZ or recurrent GBM (Arm B) or as monotherapy in patients with recurrent GBM (Arm C).1
Eligible patients in Arm C were adults with a Karnofsky Performance Status (KPS) score ≥70, EGFR amplification (confirmed centrally), recurrent GBM, normal end-organ function and no prior treatment with bevacizumab. Forty-eight EGFR-amplified recurrent GBM patients were treated in this arm. The median age was 59 years (range, 35-80). Most patients had prior therapies: 40 percent had one, 48 percent had two, and 10 percent had three or more prior therapies.1
ABT-414 is an investigational monoclonal antibody drug conjugate (ADC) targeting EGFR (epidermal growth factor receptor) developed by AbbVie researchers with components in-licensed from Life Science Pharmaceuticals, Inc. and Seattle Genetics.1 It is being evaluated for the treatment of patients with EGFR-amplified glioblastoma, an aggressive malignant primary brain tumor.1,4 In 2014, the FDA and the European Medicines Agency granted orphan drug designation for the treatment of glioblastoma and glioma, respectively.6,7ABT-414 is an investigational compound and its efficacy and safety have not been established by the FDA or any other health authority.
1 van den Bent M et al. Efficacy of a novel antibody-drug conjugate (ADC), ABT-414, as monotherapy in epidermal growth factor receptor (EGFR) amplified, recurrent glioblastoma (GBM). Poster presentation #2542; presented at the 52nd Annual Meeting of the American Society of Clinical Oncology (ASCO) in Chicago, Illinois, June 5, 2016.
2 Taylor T et al. Targeting EGFR for treatment of glioblastoma: Molecular basis to overcome resistance. Curr Cancer Drug Targets. 2012;12(3):197-209.
3 Stupp R et al. Radiotherapy plus concomitant and adjuvant temozolomide for glioblastoma. N Engl J Med. 2005;325(10):987-996.
4 Omuro A and DeAngelis L. Glioblastoma and other malignant gliomas: A clinical review. JAMA. 2013;310(17):1842-1850.
5 American Brain Tumor Association (2014). Glioblastoma (GBM). http://www.abta.org/brain-tumor-information/types-of-tumors/glioblastoma.html. Accessed on May 4, 2016.
6 U.S. Food and Drug Administration (2014). Orphan Drug Designations and Approvals. https://www.accessdata.fda.gov/scripts/opdlisting/oopd/OOPD_Results_2.cfm?Index_Number=433214. Accessed May 2016.
7 European Medicines Agency (2014). Public summary of opinion of orphan designation. http://www.ema.europa.eu/docs/en_GB/document_library/Orphan_designation/2014/09/WC500171954.pdf. Accessed May 4, 2016.
For more information http://abbvieoncology.com.