1. Metric Overview

The TriAxis Synergy Scoring Model (TSSM) is the primary quantitative metric used within the Synergistic Evaluation Framework (SEF) to measure therapeutic synergy across three critical pharmacologic axes:

1. Potency (P)
2. Precision (R)
3. Persistence (T)

TSSM evaluates whether a therapeutic system produces sustained biological pressure against a disease system while avoiding selective evolutionary pressure that generates resistance.

This metric is directly aligned with the SCF core principle of Resistance Prevention.

Within the SEF architecture, synergy is defined not simply as additive pharmacologic interaction but as a multi-axis convergence of therapeutic effectiveness across time, target specificity, and magnitude of effect.

2. Conceptual Rationale

Traditional drug synergy metrics typically measure only dose-response amplification. However, therapeutic durability in complex diseases requires simultaneous optimization of three independent dimensions:

A therapy may be potent but poorly targeted, resulting in toxicity.

Alternatively, it may be precise but transient, leading to insufficient therapeutic pressure.

The TSSM metric therefore measures the geometric convergence of these three axes.

3. Mathematical Formulation

The TriAxis Synergy Score is defined as:

$TSSM = P^{\alpha} \times R^{\beta} \times T^{\gamma}$

Where:

The exponents allow calibration of the metric depending on therapeutic area.

Typical starting values:

$\alpha = 1,\quad \beta = 1,\quad \gamma = 1$

4. Component Definitions

4.1 Potency (P)

Potency measures the magnitude of therapeutic effect relative to baseline biological activity.

$P = \frac{E_{max}}{EC_{50}}$

Where:

Higher potency results in greater therapeutic pressure on the disease system.

4.2 Precision (R)

Precision quantifies target specificity within biological networks.

$R = \frac{B_{target}}{B_{total}}$

Where:

Precision approaches 1 when the majority of drug interactions occur at disease-relevant targets.

4.3 Persistence (T)

Persistence represents the temporal stability of therapeutic activity.

$T = \frac{t_{active}}{t_{clearance}}$

Where:

Higher persistence indicates sustained therapeutic pressure.

5. Expanded TSSM Equation

Substituting component equations:

$TSSM = \left(\frac{E_{max}}{EC_{50}}\right)^{\alpha} \times \left(\frac{B_{target}}{B_{total}}\right)^{\beta} \times \left(\frac{t_{active}}{t_{clearance}}\right)^{\gamma}$

This equation integrates pharmacodynamics, pharmacokinetics, and molecular targeting into a single synergy score.

6. Interpretation of Score

High scores indicate therapies capable of exerting sustained and targeted biological pressure against disease systems.

7. Experimental Measurement

TSSM components are derived from laboratory data.

Potency

Measured using:

• dose-response curves
• IC50 / EC50 assays
• cellular viability assays

Precision

Measured using:

• receptor binding assays
• ligand-target docking studies
• proteomic interaction mapping

Persistence

Measured using:

• pharmacokinetic half-life
• time-course efficacy assays
• drug stability measurements

These measurements correspond to traditional laboratory techniques used to evaluate pharmacologic activity.

8. Example Calculation

Suppose experimental data yields:

Potency:

$P = \frac{0.90}{0.15} = 6$

Precision:

R = 0.80

Persistence:

T = 2.5

TSSM:

$TSSM = 6 \times 0.80 \times 2.5$

TSSM = 12

Interpretation: exceptionally strong therapeutic synergy.

9. Role in SCF Drug Design

Within the SCF therapeutic engineering pipeline, TSSM is used to:

• rank candidate compounds
• evaluate synergistic drug combinations
• simulate resistance barriers
• optimize therapeutic architectures

Because TSSM incorporates persistence and precision alongside potency, it serves as a predictive indicator of long-term therapeutic durability.

10. Limitations

Potential limitations include:

Future development may incorporate machine learning-based optimization of exponent parameters.

Summary

The TriAxis Synergy Scoring Model (TSSM) provides a quantitative method for evaluating therapeutic synergy across potency, precision, and persistence. By integrating these three dimensions, the metric enables rational engineering of therapies capable of sustaining biological pressure against complex disease networks while minimizing resistance development.