Key facts (25–26 Sept 2025)
- Catalyst: Plus Therapeutics’ subsidiary CNSide Diagnostics signed a national agreement with UnitedHealthcare—effective Sept. 15, 2025—to provide its CNSide® Cerebrospinal Fluid Tumor Cell Enumeration test, potentially accessible to 51+ million covered lives. [1]
- Market reaction:PSTV shares jumped as much as ~60% in premarket trading on Sept. 25 following the announcement. [2]
- Quality/performance claims: Since 2020, CNSide has been used >11,000 times at 120+ U.S. cancer centers, reporting 92% sensitivity, 95% specificity, and influencing treatment in ~90% of cases (company data). [3]
- Analyst move (Sept. 25):D. Boral Capital reiterated a Buy on PSTV with a $5 target; Nasdaq also highlighted the call. [4]
- Fresh context: In the week leading up to the deal, CNSide’s Houston lab secured CLIA accreditation—a prerequisite many payers require for broad reimbursement. [5]
- Funding backdrop (Sept. 22): Plus Therapeutics received an additional $1.9M non‑dilutive payment from CPRIT under a $17.6M grant supporting its CNS programs. [6]
- Regulatory climate for lab-developed tests (LDTs): After an April court decision vacated FDA’s 2024 LDT rule, FDA on Sept. 19, 2025 issued a new rule reverting to pre‑2024 text, easing near‑term federal uncertainties for LDTs like CNSide. [7]
What happened—and why it mattered
UnitedHealthcare coverage win. On Sept. 25, Plus Therapeutics announced that UnitedHealthcare Insurance Company (UNH) granted national coverage for its CNSide® CSF Tumor Cell Enumeration LDT for metastatic CNS cancer, effective Sept. 15. The deal potentially opens access to more than 51 million members nationwide and positions CNSide as a covered testing service for specialists treating leptomeningeal metastases (LM)—a devastating complication of advanced cancers. [8]
What the test does. The CNSide platform supports rapid diagnosis, treatment monitoring and guidance in LM. Plus Therapeutics reports >11,000 tests performed across 120+ institutions since 2020, with 92% sensitivity/95% specificity and clinical decision impact in ~90% of cases—figures that speak to potential utility vs. legacy CSF cytology. [9]
Stock jumped on the news. Investors bid PSTV sharply higher, with premarket gains of about 60% on Sept. 25 as coverage news hit traders’ screens. [10]
Accreditation paved the way. Just a week earlier (Sept. 18), CNSide’s clinical lab earned CLIA accreditation, a milestone that “ensures laboratories meet all requirements” and supports state licensure, commercial coverage and Medicare/Medicaid enrollment—in short, the plumbing you need before payers broadly reimburse a test. [11]
Cash, not dilution. On Sept. 22, Plus Therapeutics announced $1.9 million in additional CPRIT funding—part of a $17.6 million grant—bolstering the balance sheet without new shares. [12]
Expert voices
- Clinician view (UT Southwestern): “The CNSide assay is an invaluable diagnostic tool … providing important guidance in monitoring disease and helping define treatment,” said Dr. Michael Youssef in July’s U.S. launch update. [13]
- Operations view (CNSide Diagnostics): “This is a key milestone … and underscores our commitment to the highest quality standards,” said Russ Bradley, President & GM, following CLIA accreditation. [14]
(Quotes shortened for clarity; emphasis added.)
The bigger picture: where CNSide fits
Disease context. LM occurs in roughly 5% of cancer patients and is often rapidly fatal, making earlier, more sensitive detection consequential for care planning. CNSide’s positioning—enumerating tumor cells and characterizing biomarkers in CSF—aims to guide therapy more precisely than standard cytology. Plus has pegged the U.S. diagnostic opportunity at >$6B for its CSF tumor‑cell test. [15]
Corporate strategy. Plus acquired the CNSide portfolio from Biocept in 2024 and has been rebuilding commercial infrastructure. A July update outlined a Texas-first launch (August 2025) targeting NCI‑Designated Cancer Centers like MD Anderson and UT Southwestern, followed by rapid regional expansion. [16]
Regulatory status. CNSide is an LDT (laboratory‑developed test). Company materials note it has not gone through FDA clearance/approval; historically it has been run under CLIA/CAP laboratory oversight. The Sept. 19, 2025 FDA action reverting LDT regulation back to pre‑2024 language reduces immediate federal uncertainty, though state rules and payer policies still drive real‑world access. [17]
How the market reacted—and what analysts said
Price action. The UHC agreement sparked heavy interest: PSTV surged premarket by ~60% on Sept. 25. Momentum reflected both coverage‑driven revenue potential for an LDT and a relief rally in a micro‑cap name that had recently regained Nasdaq listing compliance (Aug. 26). [18]
Street coverage (Sept. 25).D. Boral Capitalmaintained a Buy with a $5 target, per GuruFocus and Nasdaq summaries, framing the UHC deal as validation of market access progress. (Consensus targets vary widely across smaller‑cap diagnostics; handle with care.) [19]
How PSTV’s news stacks up against similar 2025 diagnostics headlines
- Guardant Health (GH): In late September, Guardant announced a U.S. collaboration with Quest Diagnostics to broaden access to Shield, a blood‑based CRC screening test already covered by Medicare and the VA Community Care Network. Shield’s commercialization breadth and payer base underscore how access can scale once payers line up. [20]
- Exact Sciences (EXAS): Cologuard Plus™ launched in Q1 2025 with Medicare coverage and guideline inclusion—a reminder that payer support can rapidly lift utilization for high‑value cancer screening. [21]
- Natera (NTRA): Signatera™ continued to broaden Medicare coverage in 2025 for multiple cancers (and has ongoing commercial coverage wins), illustrating the flywheel between evidence, coverage, and adoption in oncology diagnostics. [22]
Takeaway: PSTV’s UHC agreement is directionally similar—payer endorsement → easier access → potential volume ramp. The difference is focus and scale: CNSide targets LM in advanced cancers, a serious but narrower use case than mass screening (e.g., CRC), so adoption will be more specialist‑driven. Still, national commercial coverage is a critical commercial unlock for an LDT. [23]
What to watch next
- Payer dominoes: Will other national and regional payers follow UHC with positive coverage decisions? (UHC is often a bellwether.) [24]
- Geographic expansion: Execution of CNSide’s Texas‑first rollout and state licensure footprint; the CLIA milestone suggests this is underway. [25]
- Utilization & revenue: Evidence of test adoption, reimbursement rates, and collections in upcoming quarters will reveal how coverage translates to top‑line growth. [26]
- Pipeline synergy: How CNSide integrates with Plus’s REYOBIQ™ (rhenium‑186 obisbemeda) programs in LM and recurrent GBM (potential for companion‑like positioning). [27]
- Policy stability: FDA/LDT policy remains fluid; the Sept. 19 reversion eases pressure, but labs and payers will keep adapting to any legal shifts. [28]
News timeline you asked for (25–26 Sept 2025)
- Sept. 25 – UnitedHealthcare national coverage for CNSide announced (GlobeNewswire) → PSTV spikes premarket ~60% (Investing.com). [29]
- Sept. 25 – D. Boral Capital reiterates Buy rating and $5 PT on PSTV (GuruFocus/Nasdaq). [30]
- Sept. 26 – BioSpace publishes the coverage press release, amplifying sector reach. [31]
Bottom line
For patients and clinicians, UHC coverage means fewer barriers to an LM‑focused test with higher reported sensitivity than century‑old cytology and the potential to steer treatment decisions where time is critical. For Plus Therapeutics, it’s a signature market‑access win that validates months of groundwork (CLIA accreditation, Texas launch) and opens a path from evidence → coverage → adoption in a specialized oncology niche. For investors, PSTV remains a high‑volatility micro‑cap, but the payer win plus fresh non‑dilutive funding are precisely the de‑risking steps the market has been waiting to see. [32]
Sources
- Plus Therapeutics press release: UnitedHealthcare national coverage for CNSide (Sept. 25, 2025). [33]
- Investing.com: PSTV premarket +60% on the announcement (Sept. 25, 2025). [34]
- GuruFocus/Nasdaq:D. Boral Capital maintains Buy, $5 PT (Sept. 25, 2025). [35]
- BioSpace:CLIA accreditation for CNSide lab (Sept. 18, 2025) and coverage release repost (Sept. 26, 2025). [36]
- GlobeNewswire:CPRIT $1.9M additional advance payment (Sept. 22, 2025). [37]
- FDA/Reuters:LDT rule reversion (Sept. 19, 2025) and legal backdrop. [38]
- Peer context: Guardant–Quest collaboration & payer coverage, Exact Sciences Cologuard Plus Medicare coverage/guidelines, Natera Signatera Medicare coverage expansions. [39]
This article is for informational purposes only and not investment advice.
References
1. www.globenewswire.com, 2. www.investing.com, 3. www.globenewswire.com, 4. www.gurufocus.com, 5. www.biospace.com, 6. www.globenewswire.com, 7. www.fda.gov, 8. www.globenewswire.com, 9. www.globenewswire.com, 10. www.investing.com, 11. www.biospace.com, 12. www.globenewswire.com, 13. www.globenewswire.com, 14. www.biospace.com, 15. www.globenewswire.com, 16. cnside-dx.com, 17. cnside-dx.com, 18. www.investing.com, 19. www.gurufocus.com, 20. investors.guardanthealth.com, 21. www.exactsciences.com, 22. investor.natera.com, 23. www.globenewswire.com, 24. www.globenewswire.com, 25. www.globenewswire.com, 26. www.globenewswire.com, 27. www.globenewswire.com, 28. www.fda.gov, 29. www.globenewswire.com, 30. www.gurufocus.com, 31. www.biospace.com, 32. www.globenewswire.com, 33. www.globenewswire.com, 34. www.investing.com, 35. www.gurufocus.com, 36. www.biospace.com, 37. www.globenewswire.com, 38. www.fda.gov, 39. investors.guardanthealth.com
