Funding profile · Critical care diagnostics

PreDxion Bio

A Y Combinator diagnostics company with two hard dollar figures on the public record, no Form D, and a list of named investors with no amounts attached. Here is what the record holds and what it does not.

$120KSeed recorded Aug 23, 2017, Y Combinator, per CB Insights
$224,944NIH STTR Phase I, NICHD, fiscal 2018
$130KBusiness plan competition prizes won in 2016
$0Form D offerings on file with the SEC

Data as of September 23, 2026. Company-reported figures are labeled.

Rounds at a glance

When Round Amount Investors Source
Early 2016 Michigan Business Challenge prizes $30,000 Pryor-Hale award $25,000; Williamson award $5,000 Institutional
Apr 2016 Rice Business Plan Competition $100,000 TiE Boston Angel Investment Prize Independent
2016 University grants Not disclosed Coulter Foundation; U-M Michigan Translational Research and Commercialization for Life Sciences Institutional
Aug 23, 2017 Seed, Y Combinator Summer 2017 $120,000 Y Combinator CB Insights
FY2018 NIH STTR Phase I $224,944 NICHD, award 1R41HD090759-01 Public record
By Sep 2020 Angel and institutional backing Not disclosed Y Combinator, Paul Buchheit, Invest Detroit Company site
By Aug 2021 Backer list expands Not disclosed Y Combinator, SignalFire, Hillsven, Paul Buchheit, University of Michigan Company site

What the filings show

Nothing, at the SEC. A full text search of EDGAR on September 23, 2026 returns no filing that mentions PreDxion Bio, and none that mentions Refractal, the name the company later used. There is no Form D, no amendment, and no investment vehicle formed around the company. The only federal filings that exist are a grant record and a vendor registration.

PreDxion Bio, Inc. · NIH STTR Phase I · fiscal 2018

Award
1R41HD090759-01
Amount
$224,944
Institute
NICHD
Period
Jan 1, 2018 to Sep 30, 2018
Principal investigator
Timothy T Cornell, co-founder
Purpose
Validating the MicroKine assay for identifying personalized precision therapies in pediatric sepsis
Phase II
None recorded

PREDXION BIO, INC. · federal vendor registration

Vendor ID
SAM00000000001034966
Year established
2016
Address
7455 Dexter Ann Arbor Rd, Dexter, Michigan
Contact
Walker M McHugh, chief executive officer
Classification
Small business; NAICS 334510, electromedical apparatus manufacturing
Contracts
None found

Reading the record

  1. Two numbers carry the whole capital story.$120,000 from Y Combinator in August 2017 and $224,944 from NIH in fiscal 2018. Add the 2016 prize money of $130,000 and the documented total is $474,944. Every other backer named by the company comes with no amount and no date.
  2. Three quarters of the documented money is non-dilutive.$224,944 of grant plus $130,000 of prizes is $354,944, or 75 percent of $474,944. Only the $120,000 accelerator seed bought equity on the record.
  3. The absence of a Form D is informative but not conclusive.A Rule 506 offering requires a Form D within 15 days of first sale. Companies that raise under Section 4(a)(2), or through instruments handled outside Regulation D, file nothing. So the empty EDGAR result does not prove no venture money moved. It does mean no priced round is on the public record, and it is unusual for a company that names SignalFire and Hillsven as backers.
  4. The backer list grew between two website captures.The September 7, 2020 site named Y Combinator, Paul Buchheit and Invest Detroit. The August 28, 2021 site named Y Combinator, SignalFire, Hillsven, Paul Buchheit and the University of Michigan. Two institutional names appear inside that eleven month window, which brackets a financing that has no public number, no date and no filing.
  5. The loudest promotion came from an investor, not the company.On April 24, 2020 Paul Buchheit published a post promoting an unnamed LSPR screening team as the one most ready to scale. He was already an investor. Readers on Hacker News identified the company and questioned the missing disclosure the same day. No funding announcement followed.
  6. Nothing was filed afterwards.No Form D under PreDxion Bio and none under Refractal. The last company website capture is August 28, 2021, and the domain has served online casino pages since 2023.

Commercial signals

Signal Detail Source type
Regulatory No 510(k), no PMA, and no SARS-CoV-2 emergency use authorization on any FDA list as of Sep 23, 2026. Public record
Designation FDA Breakthrough Device designation claimed for the LSPR biosensor. FDA publishes no list of designations, so it cannot be verified. Company-stated
Clinical NCT04295278, 25 patients estimated, posted Mar 2020, never recorded as recruiting, status unknown, no results. Public record
Product MicroKine described on the company site as under development, not for sale, and not intended for use in diagnostic procedures. Company-stated
Revenue No customer, contract or revenue disclosure found in any source. Not found
Corporate status Renamed Refractal. Y Combinator lists the company as Inactive with a team size of six. Public record

What to watch

  • Any Form D under Refractal or a successor entity. None exists today.
  • Whether the Michigan LSPR patents are relicensed to another operating company.
  • A status change or termination record on NCT04295278, which has sat at unknown since September 2020.
  • Whether SignalFire or Hillsven ever disclose the position, which would date the round the filings do not show.

The PreDxion Bio story on Healthcare DiscoveryHealthcare Discovery

Related companies

Sources

  1. Public recordSEC EDGAR full text search for PreDxion and for Refractal, no resultsSEC · Sep 23, 2026
  2. Public recordNIH RePORTER award 1R41HD090759-01NICHD · FY2018
  3. Public recordNIH STTR award abstract, Validating the MicroKine Assay for Pediatric SepsisInknowvation SBIR award record · 2018
  4. Public recordFederal vendor profile, PREDXION BIO, INC., Dexter, MichiganSAM registration via GovCB · accessed 2026
  5. Public recordClinicalTrials.gov NCT04295278First posted Mar 4, 2020
  6. Public recordFDA in vitro diagnostics EUA lists, antigen and molecular SARS-CoV-2 testsFDA · checked Sep 23, 2026
  7. IndependentRefractal company funding profile, formerly PreDxion BioCB Insights · accessed Sep 2026
  8. IndependentUM Student Startups Excel At Rice Biz Plan EventTechCentury · Apr 18, 2016
  9. InstitutionalBME Students Triumph in Michigan Business ChallengeUniversity of Michigan Biomedical Engineering · Mar 22, 2016
  10. InvestorA Possible Third Solution to End the PandemicPaul Buchheit · Apr 24, 2020
  11. CompanyPreDxion Bio website captures listing backerspredxionbio.com · Sep 7, 2020 and Aug 28, 2021
  12. CompanyPreDxion Bio directory entry, Summer 2017, marked InactiveY Combinator · accessed Sep 23, 2026

Compiled from SEC, NIH, FDA and other public records and published reports as of September 23, 2026. Form D notices report offerings under Regulation D; a company that raises outside Regulation D files none, so an empty EDGAR result is not proof that no capital was raised. Healthcare Venture Capital Fund holds no position in PreDxion Bio. This page is not an offer to sell or a recommendation to buy any security.