A Study of Pertuzumab With Erlotinib in Patients With Locally Advanced or Metastatic Non-Small Cell Lung Cancer (NSCLC)

A DLT was defined as: Any non-hematological toxicity ≥ Grade 3 according to the Common Terminology Criteria for Adverse Events, version 3.0, except for fever, chills, and flu-like symptoms, which occurred despite adequate participant management. The following Grade 1-3 toxicities were exempt: Grade 1-3 skin and/or epithelial toxicities consistent with erlotinib single agent therapy, unless they did not respond to treatment or dose reduction or interruption (Grade 4 skin and/or epithelial toxicities were considered to be a DLT); Grade 4 neutropenia occurring for > 7 days; febrile neutropenia which occurred despite adequate participant management; Grade 4 thrombocytopenia or any thrombocytopenia requiring platelet transfusion; and any subjectively intolerable toxicity felt by the investigator to be related to either one of the compounds.

Responders are participants who achieved either a complete response or a partial response according to Response Evaluation Criteria In Solid Tumors (RECIST) criteria. RECIST is a set of published rules that define when tumors in cancer patients improve ("respond"), stay the same ("stabilize"), or worsen ("progress") during treatment.

Complete and partial responses were determined by the Response Evaluation Criteria in Solid Tumors (RECIST) v1.1. A complete response was defined as the disappearance of all target and non-target lesions. A partial response was defined as at least a 30% decrease in the sum of the longest diameter of target lesions, taking as reference the baseline sum of the longest diameter.

Maximum Observed Plasma Concentration (Cmax), which is the maximum (peak) concentration (amount of drug) measurable in blood plasma after a dose is administered, typically measured in nanograms/milliliter (ng/mL), reported as mg/L.

The time at which maximum concentration (Cmax), which is the maximum (peak) concentration (amount of drug) measurable in blood plasma after a dose is administered, is reached (Tmax).

Terminal phase plasma half-life (t ½) is the time required to divide the plasma concentration by two after reaching pseudo-equilibrium, rather than the time required to eliminate half the administered dose.

Bioavailability [AUC(0-t)] is a measure of how much of the drug reaches the person's bloodstream from time 0 (pre-dose) to a given time point (t) for the body to use. The extent of product bioavailability is estimated by the area under the blood concentration vs time curve. The Area Under the Curve (AUC) is calculated by plotting the drug's blood levels on a graph at different times during the set period. The area under this curve reflects the amount of drug exposure in the set time period, calculated as hour * nanograms (ng) per milliliter (mL), which equates to mg.day/L. Bioavailability Extrapolated to Infinity [AUC (0-inf)] is a calculated measure of how much of the drug will ever reach the person's bloodstream for the body to use. AUC (0-inf) stands for the area under the plasma concentration versus time curve from time zero (pre-dose) to extrapolated infinite time (forever). It is obtained from calculating AUC (0-t) plus AUC (t-inf).

A fundamental concept in pharmacokinetics is drug clearance (CL), that is, elimination of drugs from the body. The clearance is simply the ratio of the dose to the area under the curve (AUC), so that the higher the AUC for a given dose, the lower the clearance. If a drug is administered by continuous infusion and a steady state is achieved, the clearance can be estimated from a single measurement of the plasma drug concentration.

Steady-state volume of distribution of a drug is an estimate of drug distribution independent of elimination processes. It is most useful for predicting the plasma concentrations following multiple dosing to a steady-state or pseudo-equilibrium. Vss is proportional to the amount of drug in the body versus the plasma concentration of the drug at steady state (pseudo-equilibrium). It is a calculated measure.