Computational Modeling of Drug Response Identifies Mutant-Specific Constraints for Dosing panRAF and MEK Inhibitors

Andrew Goetz1,2, Frances Shanahan3, Logan Brooks4

  • 1gRED Computational Sciences, Genentech, South San Francisco, CA 94080, USA.

Cancers
|August 29, 2024
PubMed
Abstract

Insights

This study used cell line data and computational models to find optimal doses for pan-RAF (Belvarafenib) and MEK (Cobimetinib) inhibitors in melanoma. Results show NRAS mutant melanoma requires a narrower, more precise drug dosage for maximum synergy.

Area of Science:

  • Oncology
  • Pharmacology
  • Computational Biology

Background:

  • Drug combinations are crucial for enhancing anti-cancer efficacy in melanoma.
  • Optimal dosing strategies for combined targeted therapies remain an area needing further investigation.
  • Understanding differential responses in NRAS vs. BRAF mutant melanoma is key for personalized treatment.

Purpose of the Study:

  • To identify optimal dosage requirements for pan-RAF (Belvarafenib) and MEK (Cobimetinib) inhibitors in melanoma using in vitro cell line data and computational modeling.
  • To investigate the differential synergistic effects and dosage landscapes of these inhibitors in NRAS-mutant versus BRAF-mutant melanoma.
  • To establish a framework for selecting effective drug combination dosages to maximize anti-cancer responses.

Main Methods:

  • Conducted a drug combination screen across 43 melanoma cell lines to determine dosage landscapes for pan-RAF and MEK inhibitors.
  • Employed computational modeling and molecular experiments to elucidate mechanisms underlying differential drug responses.
  • Validated in vitro dose-response maps by predicting tumor growth in xenografts and analyzing clinical trial data.

Main Results:

  • Identified distinct dosage landscapes for pan-RAF and MEK inhibitors in NRAS vs. BRAF mutant melanomas, with NRAS mutants showing greater synergy within a narrower dose range.
  • Attributed differential responses to adaptive resistance via negative feedback mechanisms, elucidated through computational and molecular studies.
  • Demonstrated high accuracy in predicting in vivo tumor responses (cytostatic and cytotoxic) from in vitro data and confirmed stricter dose constraints for NRAS mutant melanoma patients in clinical trials.

Conclusions:

  • Pre-clinical data and computational modeling can effectively guide dosage strategies for optimizing synergy in melanoma drug combinations.
  • The study highlights the critical need for precise dosing, particularly in NRAS-mutant melanoma, to achieve therapeutic benefits.
  • A framework is proposed to aid dose selection in drug combinations, addressing real-world challenges of maintaining optimal therapeutic windows.

Related Concept Videos

mTOR Signaling and Cancer Progression03:03

mTOR Signaling and Cancer Progression

The mammalian target of rapamycin or mTOR protein was discovered in 1994 due to its direct interaction with rapamycin. The protein gets its name from a yeast homolog called TOR. The mTOR protein complex in mammalian cells plays a major role in balancing anabolic processes such as the synthesis of proteins, lipids, and nucleotides and catabolic processes, such as autophagy in response to environmental cues, such as availability of nutrients and growth factors.
The mTOR pathway or the...
Mouse Models of Cancer Study02:43

Mouse Models of Cancer Study

Mice have long served as models for studying human biology and pathology because of their phylogenetic and physiological similarity with humans. They are also easy to maintain and breed in the laboratory, and hence, many inbred strains are now available for research. Studies on mice have contributed immeasurably to our understanding of cancer biology.
The development of transgenic, knockout, and knock-in mice has led to an exponential increase in their use as model organisms in research,...
Combination Therapies and Personalized Medicine02:50

Combination Therapies and Personalized Medicine

Combining two or more treatment methods increases the life span of cancer patients while reducing damage to vital organs or tissue from the overuse of a single treatment. Combination therapy also targets different cancer-inducing pathways, thus reducing the chances of developing resistance to treatment.
The combination of the drug acetazolamide and sulforaphane is a good example of combination therapy to treat cancer. The cells in the interior of a large tumor often die due to the hypoxic and...
Pharmacodynamic Models: Direct Effect Model and Indirect Response Model01:29

Pharmacodynamic Models: Direct Effect Model and Indirect Response Model

Pharmacodynamic models are essential tools in understanding the relationship between drug concentrations and their effects on biological systems. By characterizing the dynamics of drug action, these models guide dose selection, optimize therapeutic efficacy, and inform the development of new drugs. Two major classes of pharmacodynamic models include direct effect and indirect response models.Direct Effect ModelsDirect effect models describe the immediate relationship between drug concentration...
Impact of Pharmacokinetic–Pharmacodynamic Models: Regulatory Decisions01:15

Impact of Pharmacokinetic–Pharmacodynamic Models: Regulatory Decisions

PK–PD modeling has significantly influenced FDA regulatory decisions, particularly drug approval, dosage optimization, and labeling. These models integrate pharmacokinetics (PK) and pharmacodynamics (PD) to predict drug behavior and effects, aiding in optimizing dosing regimens and enhancing the probability of clinical trial success.One notable example is Nesiritide (Natrecor®), a recombinant human brain natriuretic peptide for treating acute decompensated congestive heart failure (CHF).