Pharmacokinetic models for first-in-human dose selection of immune-activating products in oncology.

Pharmacokinetic (PK) models are increasingly submitted to the FDA to support first-in-human (FIH) dose selection of immune-oncology products. To examine whether a simple PK modeling (SPM) using clearance for scaling was acceptable for dose estimation, FIH doses were computed and compared to doses that were safely administered to patients. We concluded that the SPM approach is acceptable in FIH dose estimation, but the variables should be carefully selected for CD3 constructs.

FDA Approval Summary: Cabozantinib for Differentiated Thyroid Cancer.

On September 17, 2021, the FDA approved cabozantinib (Cabometyx; Exelixis, Inc.) for the treatment of adult and pediatric patients 12 years of age and older with locally advanced or metastatic differentiated thyroid cancer (DTC) that has progressed following prior VEGFR-targeted therapy and who are radioactive iodine (RAI)-refractory or ineligible. This is the first approval for patients with RAI-refractory locally advanced or metastatic DTC who have progressed following prior therapy and the first approval in pediatric patients with DTC.

FDA Approval Summary: Margetuximab plus Chemotherapy for Advanced or Metastatic HER2-Positive Breast Cancer.

On December 16, 2020, the FDA granted regular approval to margetuximab-cmkb (MARGENZA), in combination with chemotherapy, for the treatment of adult patients with HER2-positive (HER2+) metastatic breast cancer who have received two or more prior anti-HER2 regimens, at least one of which was for metastatic disease. Approval was based on data from SOPHIA, a multicenter, randomized, open-label, active controlled study comparing margetuximab with trastuzumab, in combination with chemotherapy. The primary efficacy endpoint was progression-free survival (PFS) by blinded independent central review.

Summary of a workshop on preclinical and translational safety assessment of CD3 bispecifics.

Currently, there is a multitude of CD3 bispecifics with different molecular designs and binding properties in preclinical and clinical development for the treatment of liquid or solid tumors. The key safety concerns with CD3 bispecifics are excessive release of cytokines, which may translate to potentially life-threating cytokine release syndrome (CRS), target organ toxicity due to redirection of T-cells to normal tissues expressing the tumor-associated antigen (TAA) (off-tumor/on-target cytotoxicity), and, in some instances, neurotoxicity. Another key challenge is to arrive at a safe clinical starting dose and an efficient escalating strategy that allows patients in early dose cohorts the potential for clinical benefit in Phase 1 trials.

An FDA analysis of clinical hold deficiencies affecting investigational new drug applications for oncology products.

A systematic analysis of new commercial investigational new drug applications (IND) submitted to the FDA's Office of Hematology and Oncology Products (OHOP) in the Center for Drug Evaluation and Research was conducted to quantify the most common reasons INDs for oncology indications go on clinical hold. In OHOP, less than 10% of INDs went on hold or were withdrawn within the 30-day safety review period. Of INDs that were placed on hold, deficiencies were mainly clinical, followed by concerns related to pharmaceutical quality and nonclinical development.

An FDA oncology analysis of toxicities associated with PBD-containing antibody-drug conjugates.

With a new generation of antibody-drug conjugates (ADCs) that contain a drug-to-antibody ratio (DAR) of 2, the question remains whether advances in technology have resulted in more stable and tumor-specific ADCs. These ADCs are anticipated to cause minimal systemic exposures of payloads, with toxicities being evident mainly at tumor sites. We examined 15 ADCs with PBD-dimer payloads and a DAR of 2 and concluded that dose limiting toxicities in animals and in humans are generally related to the payload.

An FDA oncology analysis of CD3 bispecific constructs and first-in-human dose selection.

We retrospectively examined the nonclinical studies conducted with 17 CD3 bispecific constructs in support of first-in-human (FIH) trials in oncology. We also collected information on the design of dose-finding clinical trials. Sponsors have used different MABEL approaches for FIH dose selection.

An FDA oncology analysis of immune activating products and first-in-human dose selection.

As sub-therapeutic doses are not medically justifiable in patients with cancer, we retrospectively analyzed data on immune activating products, to assess approaches used in first-in-human (FIH) dose selection, the utility of animal toxicology studies in dose selection, and the length of time to complete FIH trials. The information collected included pharmacology and toxicology data, FIH dose and rationale, and dose-finding trial design. We used the principles of the Hill equation to estimate the FIH doses for antibodies and compared them to the doses administered to patients with acceptable toxicities.

An FDA oncology analysis of antibody-drug conjugates.

Antibody-drug conjugates (ADCs) are complex molecules composed of monoclonal antibodies conjugated to potent cytotoxic agents through chemical linkers. Because of this complexity, sponsors have used different approaches for the design of nonclinical studies to support the safety evaluation of ADCs and first-in-human (FIH) dose selection. We analyzed this data with the goal of describing the relationship between nonclinical study results and Phase 1 study outcomes.

Tasigna for chronic and accelerated phase Philadelphia chromosome--positive chronic myelogenous leukemia resistant to or intolerant of imatinib.

Purpose: This Food and Drug Administration (FDA) approval report describes the data and analyses leading to the approval by the FDA of nilotinib (Tasigna, AMN-107; Novartis Pharmaceuticals Corporation), an inhibitor of Bcr-Abl tyrosine kinase, for the treatment of chronic-phase (CP) and accelerated-phase (AP) chronic myelogenous leukemia (CML) resistant to or intolerant of imatinib.

Experimental Design: The FDA approval of the efficacy and safety of nilotinib was based on the results of an ongoing single-arm, open-label, phase 2 clinical trial. The primary end point for CML-CP was unconfirmed major cytogenetic response.

Workgroup report: Review of genomics data based on experience with mock submissions--view of the CDER Pharmacology Toxicology Nonclinical Pharmacogenomics Subcommittee.

Over the past few years, both the U.S. Food and Drug Administration (FDA) and the pharmaceutical industry have recognized the potential importance of pharmacogenomics and toxicogenomics to drug development.

Application of emerging technologies in toxicology and safety assessment: regulatory perspectives.

Emerging technologies applied in the regulatory field encompass a group of technologies that are used in addition to or in replacement of the standard toxicology studies conducted to support an Investigational New Drug Application (IND) or New Drug Application (NDA). The standard package includes general toxicology studies of various duration, safety pharmacology studies, genetic toxicology studies, and reproductive toxicology studies. New and emerging technologies applied to the regulation of new drugs include the use of novel biomarkers, transfected cells and transgenic animals, and the "omics" technologies (toxicogenomics, proteomics, and metabonomics).

Approval summary: azacitidine for treatment of myelodysplastic syndrome subtypes.

Purpose: This article summarizes data submitted to the U.S. Food and Drug Administration for marketing approval of azacitidine as injectable suspension (Vidaza, Pharmion Corporation, Boulder, CO) for treatment of patients with myelodysplastic syndrome.