TippingPoint Biosciences — Seed Extension — Dossier

One-Liner & Thesis

TippingPoint is building the first scalable platform to discover small molecules that selectively kill cells driven by disease-specific chromatin states, with its lead program in DIPG — a uniformly fatal pediatric brain cancer with no curative therapy. The wedge is a chromatin-state screening engine co-invented by founder Laura Hsieh that turns aberrant epigenetic signaling into a tractable drug discovery handle, beginning with a tumor type where biology forces the answer to be epigenetic.

Existing seed investors (StoryHouse among them, $600K at a $14.4M post in Feb 2026) are now being asked to follow on into a $5M Seed Extension at a $19.2M pre / $24.2M post — a modest up round from the $1.05 Series Seed price. The new wrinkle is the lead: Persephoni BioPartners (PBP), a venture studio committing $1.0–1.5M and pulling together the $3M minimum close, in exchange for a 10.8% (fully vested) common warrant funding a fractional COO / CMO / CBO / Program Lead and a new board director (Bill Heath, 36-year Lilly veteran). The deal is non-binding, the term sheet expired June 22, and the full board decision lands at the July 21 meeting.

Founders

Laura Hsieh, PhD

Founder & CEO

Trained in chromatin biology and epigenetic regulation (BA Scripps; PhD University of Washington / Fred Hutch; postdoc UCSF). Co-inventor of TippingPoint's chromatin-state drug discovery platform and named on the underlying patents. Has raised $6.5M+ to date, won SBIR support, and collected ACS Postdoctoral Fellow and Golden Ticket recognitions from ONO, AbbVie, and Astellas.

LinkedIn laura.hsieh@tippingpointbiosciences.com

Philamer Calses, PhD

Co-Founder

Co-founder of TippingPoint Biosciences and contributor to the company's chromatin-state platform alongside Laura Hsieh.

Open Questions & Risks

Unproven venture studio: Persephoni BioPartners is new and unbattle-tested as a lead. The deal leans on a milestone-vested warrant and a 90-day-notice termination right to mitigate, but the company is still bringing in an outside studio at the formative moment between Seed and Series A.
Dilution stack on a small round: A fully-vested PBP warrant of 10.8% (pre-Capital Investment) plus a board-approved option pool increase plus new Seed Extension shares is a heavy combined dilution event on a $5M raise — the up round only partially offsets it. Worth modeling pro-forma cap table before signing.
Service-fee burden: Up to $440K/year cost-plus to PBP for fractional executives, billed quarterly once the $3M minimum closes. That is ~9% of round size annually before any program spend, and assumes the fractional team delivers value Laura cannot get cheaper.
Capital concentration risk: If PBP cannot pull together the $3M minimum by Nov 30, 2026, the Investment Milestone (1.80%) and downstream milestones do not vest — but the round also does not close. The deal is structurally tied to PBP's ability to deliver co-investors, not just its own check.
Term-sheet timing pressure: Non-binding TS expired June 22; Laura intended to sign that day to preserve optionality. Definitive agreements and the studio close are punted to the July 21 board meeting, which is the real decision point — not signature of the non-binding term sheet.

Next Steps

Attend / dial into the PBP meeting on Monday, June 22 (11:30am–1pm at BIO) if available, ahead of TS signature.
Model pro-forma cap table including PBP warrant (fully vested), option pool increase, and $5M Seed Extension shares before the July 21 board meeting.
Diligence PBP team — particularly Bill Heath's incoming board role and the Lilly BD pathway he is already supporting — and reference Hilary Schultz's prior Nucleate Bio work.
Formal board decision on proceeding to Studio Closing and definitive agreements: July 21 board meeting.

Latest Meeting Notes

2026-06-22 Email · board memo Laura asks board to back revised Persephoni studio terms

CEO Laura Hsieh writes Keith and Matthew ahead of the June 22 PBP meeting at BIO to lay out the revised, non-binding term sheet for a $5M Seed Extension led by Persephoni BioPartners. She frames the studio deal as the path to a second indication, real AI on the platform, and Series A-grade BD infrastructure, and walks through how each of the board's prior concerns has been addressed.

Round structure: $5M Seed Extension at $19.2M pre / $1.10 per share (up round from $1.05 Series Seed); $3M minimum close; PBP committing $1.0–1.5M as lead.
PBP economics: Warrant for 1,766,745 common shares (~10.8% if fully vested) at $0.15/share, in four tranches — 1.80% time-based over 4 years; 1.80% on $3M close by Nov 30, 2026; 3.60% on a non-Lilly pharma BD deal >$2M of value; 3.60% on advancing a second (non-DIPG) indication to in vivo PoC.
Service fees: Cost-plus cap of $440K/yr for fractional COO (Bruce Ricart, ex-Lilly/Vor/bluebird), CMO (Maryam Mokhtarzadeh, ex-FDA Sr Medical Officer / REGENXBIO), CBO (Christopher Potts, IP lawyer), Program Lead (Sarra Djemil, ex-NCI SBIR — also TippingPoint's prior NCI program officer), and Executive Sponsor Hilary Schultz (Persephoni CEO, ex-Nucleate Bio).
Governance: Bill Heath (36 years at Eli Lilly, ex-GVP of Lilly Research Labs) joins the board once PBP invests $1M+. Warrant expires 10 years from Studio Closing or 90 days post-termination, whichever first.
Addressing prior concerns: Studio risk mitigated via milestone-vested equity and 90-day termination-for-convenience right; common-stock concern addressed by switching to a warrant capped by fractional-hire economics; capital-commitment concern addressed by tying 1.80% of the warrant to PBP actually closing $3M.
Next step: Laura intends to sign the non-binding TS on Monday June 22 (day it expires); definitive agreements and Studio Closing decision deferred to the July 21 board meeting.

Source: Meeting Notes reckyfRYZbEhoJxYo

One-Liner & Thesis

Deal Box

Company Snapshot

Founders

Open Questions & Risks

Next Steps

Latest Meeting Notes

Deal Timeline