US$32.5 million in cash, 7.42 million shares What did Hengrui actually keep in BHB-1893?

The "US$65 million upfront" figure comes from the announcement framing: US$32.5 million in cash plus US$32.5 million in shares. The IPO filing uses accounting framing: the 32.5 million preferred shares were recorded at a fair value of US$0.79, or US$25.7 million, so total upfront is recorded as US$58.2 million. Neither framing is wrong, but when comparing deals one should state which is being used.

The milestone structure is also clearer than in the announcement: technology transfer and development milestones are capped at US$23 million in total, commercial milestones at US$1 billion. The announcement's "development and commercial milestones of up to US$1.013 billion" broadly matches this, just with the technology transfer piece broken out separately.

More noteworthy is what has already happened: a US$3 million technology transfer milestone was achieved in December 2025, and a US$6 million manufacturing technology transfer milestone in March 2026, the latter paid in May 2026. In other words, the cash Hengrui has actually received since signing is US$32.5 million plus US$9 million, or US$41.5 million in total. Technology transfer is not a notional clause hanging in the future; it is being executed and paid on schedule.

The royalty line had previously been widely written as "rate undisclosed"; now there is a clear answer: tiered rates of 5% to 10% on annual net sales, with customary reduction clauses. The royalty term is calculated product by product and country by country, taking the latest of patent expiry, expiry of regulatory exclusivity, or ten years from first commercial sale — a formulation relatively favorable to the licensor, meaning that even if patents lapse early there is still a ten-year floor.

With the consideration unpacked, the question of signing timing has not gone away.

• 2025-08-11 — China obstructive HCM Phase 3 starts, 216 patients — 23 days before the agreement became effective
• 2025-09-03 effective / 09-05 announced · Core event — Exclusive license agreement: US$32.5 million cash + 32.5 million preferred shares
  Public clinical evidence at the time went only as far as Phase 1
• 2025-11-05 — Licensee formally debuts with a US$185 million Series A — first technology transfer milestone of US$3 million achieved in December
• 2026-03-30 — Obstructive Phase 2 results released, 42 patients, open-label — manufacturing technology transfer milestone of US$6 million achieved the same month
• 2026-05-05 / 05-11 — Competitor's non-obstructive Phase 3 positive; this product's non-obstructive Phase 2 released six days later — the order in this indication is settled
• 2026-06-03 — The 25% tier window for flip-proceeds sharing expires — nine months after the effective date
• 2026-08-06 — Licensee lists on Nasdaq, raising US$382.5 million — the IPO itself does not constitute a flip transaction
• 2026-09 (registry estimate) — China Phase 3 primary completion — determines the timing of the China filing
• 2027-03-03 — Flip-proceeds sharing clause expires entirely — lapses earlier if the licensee first starts its own clinical trial

Both Phase 2 readouts came after the agreement took effect, roughly seven and eight months later respectively. The new disclosures have not changed this.

But a fair word is also needed. At signing, public clinical evidence only went as far as Phase 1; the licensee took on the full risk that Phase 2 might disappoint, and in this class that risk is far from hypothetical — BMS's mavacamten Phase 3 in the non-obstructive population, ODYSSEY-HCM, announced on April 14, 2025 that it had missed its 48-week dual primary endpoints. Risk transfer comes at a price. And judging from the shareholding that later came to light, Hengrui did not simply take the cash and walk away.

HRS-1893 is a selective, reversible, non-covalent inhibitor of cardiac myosin ATPase, given as an oral tablet. The logic is straightforward: the core pathology of HCM is cardiac hypercontractility; dialing down the frequency of myosin–actin binding brings contractility back down and relieves outflow tract obstruction.

This path has already been walked successfully twice. BMS's mavacamten was the world's first approved cardiac myosin inhibitor, approved in China in 2024 and added to that year's National Reimbursement Drug List (NRDL), effective January 1, 2025. Cytokinetics' aficamten was the second, announced as approved by China's regulator on December 17, 2025 for adults with NYHA class II–III obstructive HCM, marketed in China as Xingshuping® (aficamten); its Greater China rights were acquired by Sanofi from Ji Xing Pharmaceuticals in December 2024; in February 2026 it was also approved in the EU.

So the accurate statement is: the druggability and clinical feasibility of the cardiac myosin inhibitor class have been validated by two registrations. But this does not mean that the development risk of this molecule has been cleared. The IPO filing puts it bluntly: all clinical trials of BHB-1893 completed to date were designed, sponsored and conducted by Hengrui, mainly in China, with one Phase 1 study in Australia, and the licensee did not participate in the design, conduct or oversight of those trials. The global pivotal study has not yet started.

That is the real distance between "target validated" and "molecule de-risked". The former was paid for by someone else; the latter still has to be earned.

The molecule's most solid selling point is speed of onset.

In the Phase 1 study presented at the 2025 European Society of Cardiology Congress, obstructive patients saw mean resting LVOT gradient fall by 91.0% by Day 5, from 71.2 mmHg to 6.0 mmHg; the Valsalva gradient fell by 87.4%, from 66.6 mmHg to 8.0 mmHg. Pharmacokinetic steady state was reached by Day 8. A dose-related decline in ejection fraction was observed in healthy volunteers, and on that basis investigators set 60 mg as the starting dose for patients.

Phase 2 results in the obstructive population were released on March 30, 2026: 42 patients, multicenter, randomized, open-label, 12 weeks, three titration arms. The proportion achieving complete response (gradient below 30 mmHg) ranged from 50% to 86%, with effects visible by Day 5; mean ejection fraction fell by 1.8% to 2.7%, no patient dropped below 55%, and no one discontinued due to adverse events.

Phase 2 results in the non-obstructive population were released on May 11, 2026: 84 patients, multicenter, randomized, double-blind, placebo-controlled. There is a framing issue that must be stated plainly here — the primary endpoint of this study was safety and tolerability, not efficacy. Every efficacy figure is secondary or exploratory.

In the IPO filing, the licensee summarizes the molecule's differentiation with a coined phrase — the "ejection fraction tax". Its argument: in the Phase 3 studies of both incumbent drugs, gradient reduction always came with a dose-related decline in ejection fraction, so some patients hit the ejection fraction safety threshold before reaching complete response; per its citations, aficamten's complete response rate at Week 24 was 49%, and mavacamten's at Week 30 was 57%. Hence current use requires multi-step titration and frequent echocardiographic monitoring.

The narrative is internally consistent, but two things must be flagged: these figures come from different studies at different time points and are not comparable with this product's Phase 2 figure of 50%–86%; and "reducing titration and monitoring burden" is currently a product positioning, not wording in any label.

Putting these together, the reasonable judgment is: the molecule's pharmacodynamic signal is clean, with biomarkers, cardiac structure and diastolic function all moving in the right direction; on clinical benefit, what it has is directional evidence at Phase 2 scale. The two Phase 2 studies enrolled 42 and 84 patients respectively, and the obstructive one was open-label, so effect sizes are likely optimistic and Phase 3 expectations should be actively revised downward.

One more figure deserves to be singled out: the obstructive Phase 2 started in August 2024 and reached primary completion in November; Phase 3 started in August 2025 with a registered primary completion of September 2026. Only nine months separated Phase 2 completion from Phase 3 initiation. This speed comes from the high concentration of HCM care in China — patients are mainly in tertiary hospital cardiology departments and cardiomyopathy specialty centers, and the same set of trial sites can be reused across multiple studies. Six workstreams — Phase 1, Phase 2, Phase 3, long-term safety, heart-failure expansion and CMC bridging — run simultaneously on one network, and this is the capability of domestic assets most easily underestimated by outsiders.

Before talking about the market, get the denominator right, because the most common misjudgment about this disease happens right here.

Published reviews put the number of HCM patients in China at more than 1 million, with an echocardiographic detection rate of about 0.29% in 2023; the US figure cited by the licensee in its IPO filing is more than 700,000 people. It should be noted, though, that China lacks large-scale population-based epidemiological studies of this disease, so the figure is an estimate rather than registry data; and it is the "prevalent population", not the "addressable population".

Three funnels lie between the two. The first is diagnosis: echocardiography is the primary diagnostic tool, but it depends on operator experience and equipment, so missed and delayed diagnosis is quite common. The second is subtype: only patients with outflow tract obstruction fall within the labels of the two current incumbents. The third is symptom class: current labels are limited to symptomatic patients in NYHA class II–III.

After passing through all three funnels, the population that can actually be prescribed is far smaller than a million. That is why the licensee cites a figure from another angle — current therapies have penetrated less than 20% of eligible obstructive patients. This statement is not about how large the market is, but about how many people remain untreated. For a latecomer this is actually the more compelling narrative: what is up for grabs is not just existing share, but bringing untreated patients in.

But in China, the precondition for doing this is primary-care echocardiography capacity and specialty disease recognition, not sales force size. Without shoring up that layer, "low penetration" is just a nice-sounding phrase. Using it to drive peak sales forecasts is the most common valuation trap for small-population products of this kind.

Non-obstructive HCM has long been regarded as the biggest open field in this class: patients have no outflow obstruction, so the gradient surrogate endpoint does not apply and improvement in symptoms and exercise capacity must be demonstrated directly.

On April 14, 2025, BMS announced that mavacamten's ODYSSEY-HCM missed its dual primary endpoints. The study enrolled 580 symptomatic non-obstructive patients; the dual primary endpoints were change in KCCQ Clinical Summary Score and peak VO₂ from baseline to Week 48. Secondary analyses showed improvements in biomarkers and echocardiographic remodeling measures, but the functional and symptom endpoints did not come through.

On May 5, 2026, Cytokinetics announced that aficamten's ACACIA-HCM met its dual primary endpoints: 516 patients, randomized 1:1; at Week 36, the between-group difference in KCCQ Clinical Summary Score was +3.0 (p=0.021) and in peak VO₂ +0.67 mL/kg/min (p=0.003). On safety, 10% had ejection fraction below 50% vs 1% on placebo; two patients on drug had serious heart-failure events with ejection fraction below 50%.

An equally important discipline: this product's Phase 2 KCCQ +5.5 points and peak VO₂ +0.9 mL/kg/min cannot be compared directly with ACACIA-HCM's +3.0 and +0.67. The sample sizes differ roughly six-fold; follow-up duration, enrolled populations and statistical framing all differ; and the primary endpoint of this product's study was safety and tolerability. The only thing a cross-trial comparison can say here is that effect sizes in this indication are generally modest, and nobody has produced overwhelming numbers.

Conversely, that is the challenger's only remaining opportunity — but it has to be proven by a precisely designed Phase 3, not a pretty Phase 2.

Hengrui retained Greater China and, under the agreement, bears all responsibility and cost for development, registration, manufacturing and commercialization in that territory. This part belongs entirely to Hengrui, but the numbers need to be worked out.

HRS-1893's China timeline: the obstructive Phase 3 started on August 11, 2025, with 216 patients and a registered primary completion date of September 2026. On a normal review timeline, the marketing application could be filed in 2027 at the earliest, with approval around 2028. By then mavacamten will have been on the NRDL for three to four years.

A common statement needs correcting here. It is not the case that "two rounds of negotiation have already nailed down the price anchor" — only mavacamten has actually completed NRDL negotiation and entered the list; aficamten was only approved in December 2025, after that year's list update, and as of writing there is no public negotiation outcome. The accurate statement is: this class in China already has a payment reference set by mavacamten, while aficamten's pricing and access pathway are still taking shape. For a third entrant, compression of pricing room is a trend, not a fait accompli.

On expedited pathways, no Breakthrough Therapy Designation or priority review notice for this product was found through public channels. "Not found" does not mean "does not exist"; this needs to be checked directly on the drug review agency's public notice pages. Logically, with two approved drugs already in the obstructive indication, the urgent clinical need rationale for acceleration is weakened; by contrast, the non-obstructive indication still has no approved drug in China, and if filed separately it has a better chance of regaining expedited eligibility.

Hengrui's 2025 revenue was RMB 31.629 billion, up 13.02% year on year; net profit attributable to shareholders was RMB 7.711 billion, up 21.69%; R&D spending was RMB 8.724 billion, over 27% of revenue; innovative drug sales were RMB 16.342 billion, up 26.09%; out-licensing income was RMB 3.392 billion, up 25.62%. Its commercial network covers more than 25,000 hospitals and 200,000 retail pharmacies. In cardiovascular, it already had its first Class 1 innovative drug, recaticimab (Aixin'an®), in January 2025 — the world's first ultra-long-acting PCSK9 antibody, dosable as infrequently as every 8 weeks.

This is the most concrete meaning of "platform amplifies product": HCM patients are highly concentrated in tertiary hospital cardiology departments and specialty centers, the number of target hospitals is limited, and it is one of the few diseases that can be "fully covered". Once the team, formulary committee channels and academic resources have already been built for a lipid-lowering product, the marginal selling cost of adding a cardiomyopathy product is very low. For a small-population product, this is almost the only way to make the numbers work.

But this lever has two limits. First, the synergy stays at the channel level rather than the prescribing level: the prescriber profiles for lipid-lowering and cardiomyopathy do not overlap; sharing a team saves call costs but does not create prescribing linkage; and when the same team carries a product with far larger sales, the small-population product being sidelined is a common outcome. Second, comparative evidence on the payer side is empty: there is no head-to-head study against the incumbents and no public Chinese pharmacoeconomic evidence, while the comparator in negotiation is precisely the same-class drug already on the list. The cost structure of an oral small molecule supports trading price for volume, but if the entire cost advantage is ceded to the payer, even large scale will struggle to turn into profit.

A bioequivalence study between two formulations started on April 14, 2026, with 58 subjects and expected primary completion in July — two months before the China Phase 3 primary completion. This indicates a change between the clinical formulation and the intended commercial formulation, with the bridging scheduled ahead of the key readout. This is standard practice, but if equivalence is not achieved, the CMC dossier for the China marketing application would have to be reorganized.

A human mass-balance study is also running in parallel. Together with the previously completed verapamil interaction study (14 subjects) and the food-effect and relative bioavailability study (38 subjects), the completeness of this clinical pharmacology package shows the company is building its dossier to global standards rather than minimum requirements. The interaction piece is especially critical — HCM patients routinely take beta-blockers and calcium channel blockers, verapamil being among the most commonly used, and the results will go directly into the label.

On supply, the prevailing speculation had been that "Hengrui will be replaced once technology transfer is complete". The IPO filing states the opposite: Hengrui is currently the sole manufacturer of BHB-1893. The two parties signed a separate clinical supply agreement under which Hengrui manufactures and supplies clinical trial material for the licensee's territory; Hengrui is also obliged to complete manufacturing process and CMC technology transfer on an agreed plan, at Hengrui's own cost.

This flips the direction of risk. For Hengrui, it means supply revenue will continue for the foreseeable future; for the licensee, a single Chinese supply source is a major exposure it lists in its own risk factors — covering trade and tariffs, import/export controls, and the biosecurity provisions that took effect with the US National Defense Authorization Act in December 2025. In other words, the truly vulnerable party in this relationship is not necessarily the seller.

The scope of the license is indeed broad: covering HRS-1893 and related compounds, for any use, exclusive worldwide development, manufacturing and commercialization outside mainland China, Hong Kong, Macau and Taiwan, with the right to sublicense. This also settles an earlier open question — overseas rights to new indications such as HFpEF were always within the scope of the license, so there is no need to wait for the agreement text to decide.

But "broad scope" does not mean "the seller handed over everything". The agreement contains at least five constraints with real teeth:

First, diligence obligations. The licensee must use commercially reasonable efforts to obtain approval for at least one licensed product in the United States and at least three European countries, and to commercialize it after approval. This is an enforceable hard obligation, not a soft commitment.

Second, termination rights. Either party may terminate upon the other's uncured material breach within the cure period or insolvency; if Hengrui terminates because of, among other things, the licensee's uncured willful material breach, Hengrui retains a perpetual, irrevocable, royalty-free license to continue developing and commercializing the compounds and products as of termination. In addition, if the licensee, its affiliates or sublicensees challenge the licensed patents, Hengrui may terminate the agreement in its entirety.

Third, two-way data sharing. Clinical, non-clinical and patient data, as well as CMC and manufacturing process information, held by Hengrui or generated during the term are transferred to and remain accessible to the licensee; likewise, Hengrui has the right to use data generated by the licensee in its territory for development and commercialization in Greater China. This is valuable for China registration — data from the overseas Phase 3 can directly serve later Chinese indications.

Fourth, cross-exclusivity. During the agreed exclusivity period, neither party may develop or commercialize a competing product directed at the same biological pathway.

Fifth, sharing of flip proceeds. This is the most overlooked clause, and the one that most needs explaining.

So the claim that there is "no re-pricing mechanism at all" does not hold — there is one, and it is written in considerable detail. But it should not be spun the other way into a thick trump card: it has a time limit and a high return threshold (sharing only starts above 2.5 to 2.75 times the Series A post-money valuation); the 25% tier has already expired; the remaining 15% applies only to sublicensing; and it lapses automatically once the licensee starts a clinical trial it sponsors itself — and the licensee has publicly said it will start its global pivotal study within 2026.

In other words, this is a guardrail against "buy it and flip it for arbitrage", not a long-term participation in upside. It is expiring naturally, as designed.

The only truly long-lived upside comes in three forms: the 8.5% equity stake, tiered royalties of 5% to 10%, and up to US$1 billion in commercial milestones. The first is subject to lock-up and future dilution; the latter two only start to pay out after the product launches.

Hengrui itself said in its announcement that this was its "second collaboration with international investment institutions in less than 18 months". Laying out its out-licensing track record makes things more interesting.

Amounts in US dollars. For this deal the upfront is shown on the IPO filing's accounting basis (cash plus fair value of equity); all other deals are on an announcement basis.

Aiolos is the extreme reference: it obtained its license in August 2023, and on January 9, 2024 GSK announced it would acquire the company for US$1 billion upfront plus up to US$400 million in regulatory milestones, closing on February 14 — about five months later. This kind of "buy it and flip it immediately" scenario is exactly what the flip-sharing guardrail in this agreement is meant to prevent.

Kailera is the most comparable deal: also a NewCo structure, with Hengrui initially holding 19.9% and about 13.6% pre-IPO; the licensee IPO'd in April 2026 at US$16, raising about US$625 million. Compared with 11.3% and 8.5% in this deal, the stake is noticeably thinner — and on the NewCo route, equity is the only part that appreciates along with the asset.

The main reasons for the difference in upfronts are data maturity and the nature of the buyer, not molecule quality: the deal with a multinational carried a US$500 million upfront, while the NewCo deals were all in the tens of millions.

Why move before the readouts? The answer most likely lies in the molecule's position in the portfolio: the China-side investment (a 216-patient Phase 3 plus a 300-patient long-term safety study) is negligible relative to annual R&D spending of RMB 8.724 billion, and the Chinese market is already occupied by incumbents. Small investment and limited expected revenue mean little motivation to fight for another round of terms. And out-licensing income has already become a predictable revenue line — RMB 3.392 billion in 2025, up 25.62%. When licensing becomes a routine line item, the objective function of negotiation drifts from "maximizing value per deal" to "deal replicability".

Listing the evidence that could overturn this article's conclusions is the more responsible thing to do for readers.

On the value of the stake. US$133.6 million is a static calculation at the US$18 offer price; it has not been monetized and does not account for sell-down discounts after lock-up expiry or dilution from future financings. If the share price falls sharply, this figure will shrink quickly; conversely, if clinical progress goes well it could end up far higher. Evaluating the deal by treating it as "realized gain" is as inaccurate as the earlier description of it as "undisclosed".

On the value of flip sharing. The sharing threshold is set at 2.5 to 2.75 times the Series A fully diluted post-money valuation, and the actual value of that valuation has not been made public. Until that number is known, it is impossible to judge whether the threshold is high or effectively meaningless. This article leans toward thinking it is high, but that is an inference.

On "having lost the first-mover position in non-obstructive HCM". ACACIA-HCM's effect size is not large (KCCQ between-group difference +3.0, peak VO₂ +0.67). If this product's global pivotal study delivers a significantly larger difference on the same endpoints, the challenger positioning could be overturned — the pioneer's premium mainly shows up as first-line guideline recommendation and pricing power, and both get redistributed when the effect-size gap is clear.

On expedited pathways in China. This article relies on the absence of relevant notices in public channels, which is not negative evidence. If the product has already obtained such designation, the China timeline could move forward as a whole and the third entrant's disadvantage would narrow markedly.

On execution risk. As of August 10, 2026, no licensee-led global pivotal study appeared in public registries. Registration usually lags internal project approval and first-patient preparation, so no record does not mean no start. The IPO has removed the funding constraint; this question will be answered within the year.

Still undisclosed are: the specific trigger events of each milestone tranche, the royalty tier breakpoints and reduction conditions, the specific arrangements for sublicense sharing, and the Series A post-money valuation. Disclosure of any one of these could change the overall judgment of the deal.

This molecule has a third indication. For heart failure with preserved ejection fraction (HFpEF), a Phase 2 study in China started on March 30, 2026, enrolling 48 patients, with a registered primary completion date of March 2027.

The patient population in this indication is an order of magnitude larger than HCM, and so far no cardiac myosin inhibitor has staked out a position there. Because the license covers "any use", overseas rights here have always belonged to the licensee; Hengrui's corresponding return is that the royalty rates apply to annual net sales of all licensed products, plus the US$1 billion commercial milestone cap — if this line works out, it is exactly the indication most likely to push the commercial milestones into the upper tiers.

But two buckets of cold water are needed. First, the mechanistic hypothesis differs from HCM — HFpEF patients do not universally have excessive contractility, so using a contractility-suppressing drug here needs stronger mechanistic justification, and a 48-patient early study is far from enough to support an expansion narrative. Second, the two parties agreed to cross-exclusivity on the same biological pathway, which means the pace of the China line cannot be fully decoupled from the overall overseas plan.