An ethical framework for the clinical use of Alzheimer’s disease biomarker testing

Blood-based Alzheimer’s biomarkers are moving from specialty settings into primary care, with commercial LDTs (e.g., C2N PrecivityAD®, Quest AD-Detect™) already available and recent regulatory milestones including FDA clearance of Roche’s Elecsys pTau181 for primary‑care use and a May 2025 510(k) for the Lumipulse G p‑tau217/β‑amyloid 1‑42 test. The paper provides a clinician-focused ethical framework emphasizing clinical utility, medical futility, informed consent, equity, and risks (psychological harm, privacy and insurance discrimination), factors that could shape adoption, reimbursement decisions, and addressable market expansion for diagnostics and downstream DMT demand.

Analysis

Market structure: Rapid primary‑care clearance and wider commercial availability of blood-based Alzheimer’s biomarkers structurally benefits large clinical lab operators and scalable assay vendors (DGX, LH) by shifting volume away from PET/CSF. Expect downward pressure on per‑test pricing (est. 10–30% over 12–24 months) but volumetric growth (+50–150% YoY initially) that should lift lab reagent and processing revenue; specialty PET providers and niche CSF diagnostics are structural losers.

Risk assessment: Key tail risks are a CMS non‑coverage decision (could cut demand 40–60% within 3–12 months), adverse real‑world performance in >80‑yr olds leading to guideline reversal, and data/privacy litigation that raises compliance costs >$50M for large labs. Immediate noise (0–30 days) around regulatory commentary; primary inflection points at 3–12 months (payer rules) and 12–36 months (DMT uptake and treatment eligibility data).

Trade implications: Tactical bias favors modest long exposure to large labs: DGX and LH capture LDT and primary‑care workflows. Use option spreads to cap downside while retaining upside: 3–6 month call spreads on DGX/LH ahead of payer decisions; small speculative 12–18 month BIIB LEAP calls (2% position) only if you expect DMT widening—otherwise short biotech exposure vs labs as a pair trade.

Contrarian angles: Consensus conflates testing volume with DMT revenue—misses eligibility and safety constraints that will cap treatment uptake to a subset (<20–30%) of biomarker‑positive patients. Historical parallel: genomic testing boom then consolidation; expect same: winners are high‑scale labs with negotiated reimbursement, not every assay vendor. Monitor reimbursement language and real‑world sensitivity by age cohort for early mispricings.

Key Decisions for Investors

• Establish a 2–3% long position in DGX (Quest Diagnostics) split into tranches: 50% now, 50% on any pullback >5% or after a favorable CMS draft within 90 days; hedge with 1:1 3‑month OTM call spread to cap cost.
• Allocate 1.5–2% long in LH (LabCorp) with a 6–9 month calendar call spread to play durable institutional contracts; trim to half position if payer guidance explicitly limits outpatient BBM reimbursement.
• Avoid outright large biotech exposure to Alzheimer’s DMT revenue; instead purchase a tactical 1% position in BIIB 12–18 month LEAP 25–30% OTM calls as binary upside (trial/label expansion), funded by selling short 1–3 month covered calls if DT volatility remains elevated (>30% implied).
• Implement a relative trade: long DGX (2%) vs short BIIB (1%) to express diagnostics adoption versus constrained DMT monetization; unwind if DGX test volume growth <20% YoY or if BIIB announces broad label expansion.
• Monitor three hard triggers in next 30–90 days and act: (1) CMS draft/NCD language (if positive, increase lab longs by +50%); (2) major carrier coverage decisions (if >2 national carriers cover, add exposure); (3) published real‑world sensitivity drops >10% in >80‑yr cohort (if triggered, reduce positions by 50%).