Investment Philosophy

First principles · Mental models · Decision frameworks

Core Belief
"If you can't explain it without jargon so anyone understands, you don't understand it well enough."
Understanding is not memorizing facts. Understanding means you can trace every claim back to first principles, predict consequences of new information, identify what would change your mind, and explain ALL of this to someone with no domain expertise without losing a single nuance. Simplification is the OUTPUT of deep understanding, not a shortcut to avoid doing the work.
The Feynman Standard
Depth First, Then Simplify
Go absurdly deep first. Read the actual papers. Understand the biology at the molecular level. THEN simplify. The simplification proves you understood. If your "simple" explanation has gaps, you didn't understand the complex version well enough. Never start with simple — that's just learning the headline without the substance.
Two Audiences, One Understanding
Expert level: To communicate in real-time with KOLs, scientists, company executives — understanding every word they say and its implications.

Non-expert level: To explain to a portfolio manager, family, friends who might buy the stock — without losing ANY nuance. If you can do both, you truly understand. If you can only do one, you don't.
Theory vs Data Reconciliation
Every mechanistic claim about a drug MUST be checked against actual clinical data. If they match, explain why biology predicted the data. If they DON'T match — that's a KEY INSIGHT. Explore possible explanations. Was the theory wrong? Is the data confounded? Never gloss over mismatches between theory and data. They are often the most valuable insights.
Drug Modality Mental Model
Target Location Determines Drug Format
WHY a drug is oral vs injectable is usually determined by WHERE the target sits. This single principle predicts the convenience profile, commercial uptake, formulary positioning, and competitive dynamics of every drug in the portfolio.
Extracellular Targets
Proteins floating between cells (TNF, IL-17, IL-23, PCSK9). Need a large antibody to grab them → injectable biologic. Too big for a pill — would be digested. Antibodies cannot cross cell membranes.
Intracellular Targets
Proteins inside cells (JAK, TYK2, PDE4, BTK, NLRP3). Need a small molecule that can pass through the cell membrane → can be oral pill. Antibodies can't reach them.
ModalityRouteDosingTarget AccessLOE RiskKey Tradeoff
Small moleculeOralDailyIntracellularGenericConvenience vs selectivity
mAbSC/IVQ2W-Q12WExtracellular onlyBiosimilar (slow)Efficacy vs convenience
PeptideSC (or oral+enhancer)Daily-weeklyExtracellularVariesIntermediate properties
siRNASCQ6MIntracellular (gene)ComplexVery long-lasting vs liver concerns
DegraderOralDailyIntracellular (destroy)GenericEliminates protein vs novel/unproven
ADCIVQ3WBoth (antibody delivers payload)ComplexTargeted delivery vs toxicity
Market Structure Models
Biology PREDICTS which market structure a disease area will have. This determines commercial value of each drug.
Replacement
Best drug wins almost all share. Homogeneous disease with one dominant pathway. Example: Keytruda in 1L NSCLC.
Split
Different patients need different drugs based on biology/subtype. Multiple drugs coexist. Example: psoriasis (IL-17 vs IL-23 vs oral suits different patients).
Sequential / Switch
Try drug A first, switch to drug B on failure. Market stratified by line of therapy. Example: LDL-lowering (statin → ezetimibe → PCSK9i).
Expansion
New drug brings in patients who weren't previously treated. Oral format for injection-averse patients. Example: oral PCSK9 (enlicitide expanding the PCSK9 market beyond injection-only).
Prescribing Dynamics
What Actually Drives Doctors to Choose Drug A Over Drug B
1. First-mover advantage and clinical comfort — doctors prescribe what they've seen work in their patients
2. Formulary positioning and payer rebates — what insurance covers most favorably
3. Guideline inclusion — when a drug makes it into treatment algorithms
4. Patient preference — oral vs injectable, frequency, side effect profile
5. Safety monitoring requirements — JAK drugs require lab monitoring = more office visits = less convenient
6. Switching inertia — "my patient is stable on drug X, why rock the boat?"

Understanding these dynamics is as important as understanding the biology. A clinically superior drug that's behind a wall of prior authorizations will lose to a slightly inferior drug that's easy to prescribe.
Data Integrity Principles
BLANK > WRONG
If you don't know the real number, leave it null. A blank field signals "needs research." A wrong number (e.g., defaulting ownership to 50/50, applying class averages to individual drugs) signals "verified" and nobody catches it. Every placeholder that looks like data is a liability.
Drug-Specific, Never Class-Level
Every drug gets its own numbers from its own trials. Never apply class-level meta-analytic averages uniformly across drugs. If all statins show "myalgia 5-10%, diabetes 9%" in your comparison table, you haven't done the work. Rosuvastatin has the highest diabetes risk; pitavastatin has none. These differences drive prescribing and are investment-relevant.
Full Interconnection
Every data change must be fully interconnected. Adding a drug means: drug record + company link + program + indication chain + mechanism + study. Adding a study result means: update program stage, drug stage, related catalysts. Never split data addition and reconciliation.
Beechwood Capital Investment Philosophy