Author of

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  P3.11 - Poster Session 3 - NSCLC Novel Therapies (ID 211)

  • Event: WCLC 2013
  • Type: Poster Session
  • Track: Medical Oncology
  • Presentations: 1
  • Moderators:
  • Coordinates: 10/30/2013, 09:30 - 16:30, Exhibit Hall, Ground Level

  • 12662

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    P3.11-014 - Safety, pharmacokinetics, and activity of the anti-NaPi2b antibody-drug conjugate DNIB0600A: A Phase I study in patients with non-small cell lung cancer and platinum-resistant ovarian cancer (ID 1477)

    09:30 - 09:30  |  Author(s): J. Xu
    • Abstract

    Background
    NaPi2b (SLC34A2) is a multi-transmembrane, sodium-dependent phosphate transporter highly expressed in non-small cell lung cancer (NSCLC) and ovarian cancer (OC). DNIB0600A is an antibody-drug conjugate consisting of a humanized anti-NaPi2b IgG1 monoclonal antibody and the anti-mitotic agent MMAE.

    Methods
    This study evaluated safety, pharmacokinetics (PK), and pharmacodynamics of DNIB0600A (0.2-2.8 mg/kg) given every 3 weeks (q3w) to patients (pts) with non-squamous NSCLC or platinum-resistant, non-mucinous OC. A traditional 3+3 design was used for dose escalation followed by expansions in NSCLC and OC at the recommended Phase 2 dose (RP2D). Tumor NaPi2b expression was evaluated in archival tissue by immunohistochemistry (IHC). Anti-tumor activity was evaluated per RECIST 1.1.

    Results
    As of 1 May 2013, 65 pts have enrolled (35 NSCLC; 30 OC), median age 62 (range 39-85), PS 0-1, median number of prior regimens 2 (1-8) in NSCLC pts, and 5 (1-12) in OC pts. Pts received a median of 4 (range 1-25) doses of DNIB0600A. One pt experienced a DLT (Grade 3 dyspnea) at 1.8 mg/kg; however, no additional DLTs occurred through the maximally administered dose of 2.8 mg/kg. Two patients had Grade 1 and 2 infusion-related reactions. The most common related AEs (all grades) were fatigue (55%), nausea (35%), peripheral neuropathy (32%), decreased appetite (29%), vomiting (25%), alopecia (20%), and diarrhea, dysgeusia, headache, and pain (each 15%). The majority of these AEs were Grade 1 and Grade 2. Two patients had serious AEs (SAE) which led to discontinuation (dyspnea; dehydration and hyperglycemia). Four other related SAEs (nausea, upper respiratory tract infection, abdominal pain, and headache) were noted in 2 pts. Preliminary PK results support a q3w dosing regimen with no accumulation observed. Expansion at 2.4 mg/kg was selected based on cumulative safety data and a benefit/risk assessment performed at time of expansion. Exposures of analytes monitored were dose-proportional over all dose levels, and no PK difference was observed between NSCLC or OC pts. Approximately 60% of NSCLC and 90% of OC pts expressed high levels (IHC 2+/3+) of NaPi2b. Anti-tumor activity with DNIB0600A was associated with tumor NaPi2b expression for both NSCLC and OC. Of the 40 pts with NaPi2b IHC Score of 2+ or 3+, treated at dose levels 1.8-2.8 mg/kg, 10 pts had a confirmed partial response (PR); 2 of 18 NSCLC and 8 of 22 OC pts, respectively. Additionally, 3 NSCLC and 3 OC pts have unconfirmed PRs. No pt was enrolled with NaPi2b IHC Score of 1+; no pt responded among the 13 pts with NaPi2b IHC Score of 0, treated at dose levels 1.8-2.8 mg/kg

    Conclusion
    DNIB0600A administered q3w has an encouraging safety, tolerability, and PK profile and evidence of anti-tumor activity in NSCLC and OC pts whose tumors express NaPi2b detectable by IHC. This data supports further clinical evaluation of DNIB0600A in NSCLC and OC together with a companion diagnostic.