One year after the ex-China license GSK paid US$1 billion to buy the licensee outright

On August 19 and 20, 2026, six Phase 3 studies were registered in two batches, all planned to start on August 31, with total planned enrollment of about 2,568 patients. This is a very heavy investment.

Three details are worth pausing on.

First, the asthma studies extend the age range down to 12. Both asthma Phase 3s enroll ages 12 to 80, including adolescents. This means going for a broader label from the start, rather than doing adults first and adding adolescents later.

Second, the COPD studies narrow the population. Both PERSIST COPD studies explicitly require "eosinophilic phenotype with elevated blood eosinophils", along with background triple or dual inhaled therapy, frequent exacerbations and elevated symptom scores.

This choice almost certainly comes from a peer's lesson. Tezepelumab's Phase 2 COURSE study in COPD enrolled a phenotype-unrestricted population, and its primary endpoint was not met — the annualized rate of moderate-to-severe exacerbations was not significantly reduced versus placebo. Subsequent analysis suggested benefit concentrated in the high-eosinophil subgroup. GSK wrote this lesson directly into the inclusion criteria.

The cost is a narrower label. Trading breadth for certainty is a clear-headed but conservative choice.

Third, and most worth noting: Phase 2 has so far published no efficacy numbers.

This needs to be stated precisely. GSK's acquisition announcement contains this sentence: "Early studies of AIO-001 have demonstrated preliminary safety, tolerability, pharmacokinetics and biological activity in healthy volunteers and patients with asthma." That is, the buyer did not have only a target and a half-life — it had at least seen biological activity signals in asthma patients.

But between "biological activity" and "how much the exacerbation rate falls" lies an entire Phase 2. Using a biomarker as the Phase 2 primary endpoint is logically coherent for an ultra-long-acting antibody whose "mechanism is validated by the same target and what really needs proving is whether exposure is sufficient"; it's just that for outside observers, at this moment when Phase 3 is about to start, there is still no quantitative basis in public channels for judging the strength of efficacy.

The chain itself is a Chinese innovative drug going-global case worth retelling again and again.

From Aiolos obtaining the license to GSK completing the acquisition was only about half a year. An antibody independently developed by a Chinese company saw its valuation multiply dozens of times without generating any new human efficacy data.

In Chinese public discussion this was once read as "Hengrui sold it cheap". But laying out the timeline gives a fairer view: what Hengrui sold was outside Greater China; it kept China for itself. And China is precisely where global competition for this target is fiercest, and the market Hengrui is most capable of fighting in itself. What's really worth discussing is not whether it sold at a loss, but the next stretch —

This is the one fact this article most wants readers to take away: for the same molecule, China already has two Phase 3 studies running, both started about a year before the global Phase 3s. And China is also pursuing a fourth indication that isn't in GSK's global plan at all — atopic dermatitis.

Sponsor of the China-side studies is Hengrui (Shanghai / Guangdong Hengrui); the Australian Phase 1 was run by its overseas subsidiary.

Another comparison is equally worth noting: Hengrui's China asthma Phase 2 uses annualized exacerbation rate directly as its primary endpoint, while GSK's global Phase 2 uses exhaled nitric oxide. On efficacy endpoints, the China line's readout is closer to a registration-grade answer, and earlier.

This Phase 2 (260 patients) has a primary completion date of December 30, 2026. If positive, it could become the earliest publicly disclosed, exacerbation-rate-based efficacy evidence for this molecule — in Hengrui's hands, not GSK's.

"Could" because there are two more variables: the China nasal polyp Phase 2 was completed in January 2026 with results not yet public; and GSK's global NAZARE Phase 2 had its primary completion on July 14, 2026, so in theory it could also be disclosed first. Who comes out first is currently uncertain.

To understand this US$1 billion, first look at what GSK already has.

Depemokimab (brand name Exdensur) is GSK's ultra-long-acting anti-IL-5 antibody, also dosed every six months. It has been approved in the US, EU, UK, Japan and China; in China it was approved for severe eosinophilic asthma in March 2026, and on April 8 additionally for chronic rhinosinusitis with nasal polyps. In other words, GSK already has a marketed "one shot every six months" respiratory biologic in China.

So what is the logic of buying another six-monthly TSLP antibody?

The answer lies in where the two targets sit on the inflammatory pathway. IL-5 governs only the eosinophil tributary; TSLP governs the upstream main gate. The ceiling of anti-IL-5 is inherently limited to eosinophil-driven patients, while TSLP can in theory cover a broader population including non-type-2 inflammation — precisely what gives the same-target competitor the confidence to set no biomarker threshold in asthma.

So GSK's portfolio intent is clear: use the same "one shot every six months" product experience to cover two layers of population, from narrow to broad. Depemokimab holds the clearly eosinophilic segment; felcorekibart goes after the broader segment, including those with unclear phenotypes. GSK labels both as ultra-long-acting in its own pipeline documents — no coincidence, but a deliberately cultivated product-family trait.

But this logic has a self-made problem: in COPD, the two assets collide.

Same company, same dosing-frequency promise, heavily overlapping target patients, and both reading out around 2029. This is not simply "one more leg" but a trade-off that will have to be made sooner or later: if both succeed, on what basis would a physician choose one for the same COPD patient? If the answer is "by eosinophil level", then the broader-population value proposition of TSLP gets cut in half by its own sibling.

There is another structural fact that is often overlooked: GSK cannot sell the asset it acquired in China. Greater China rights stayed with Hengrui from start to finish. This means that even though GSK China's respiratory team has ready-made channels, Exdensur's department network and reusable ultra-long-acting education resources, it cannot bring this molecule in. For GSK, China is a market contractually excluded from this asset — not low priority, simply out of scope.

Conversely, this also explains why Hengrui's pace in China can be so independent: it doesn't need to wait, doesn't need to coordinate, and isn't bound by the global plan's timetable. This is a genuine case of "splitting up and each running its own race".

Put the China line into its competitive environment, and things look less relaxed.

The same-target leader has just landed. Tezepelumab was approved in China in March 2026 (label approval date March 25, with severe asthma and chronic rhinosinusitis with nasal polyps approved simultaneously), and formally launched commercially on August 17. It is currently applying for the 2026 NRDL. In other words, the same-target first-mover advantage has just been established, not yet consolidated — both bad and good news for latecomers: bad in that the label and price anchor will soon be set, good in that the commercial foundation is still shallow and market education has only just begun.

A domestic same-target product has already advanced into Phase 3. TQC2731 (originated by Bosun Biologics, developed in Greater China by CTTQ) started a Phase 3 in poorly controlled severe asthma on December 3, 2024, with a primary endpoint of annualized asthma exacerbation rate at 52 weeks — the first domestic TSLP antibody to enter Phase 3 in China. There are also Keymed's CM326 (China asthma and COPD rights licensed to CSPC), Tuojie Biotech's Tavo101 and Qyuns Therapeutics' QX008N.

Counting Hengrui itself, China's TSLP lane already has at least six players. This is not an empty lane, but one that filled up before the originator even read out efficacy data.

Patient numbers aren't the problem; identifying patients is

China's disease burden is enormous. The China Pulmonary Health study shows: asthma prevalence of 4.2% among people aged 20 and over, about 45.7 million patients; about 99.9 million COPD patients aged 20 and over, with prevalence of 13.7% in those over 40.

But the same study also gives another set of numbers: 71.2% of asthma patients had not previously been correctly diagnosed, and only 23.4% had ever had a lung function test.

Together, these two sets of numbers show that the real bottleneck for biologics in respiratory disease in China has never been the drug, but that patients never reach the clinic where biologics can be used. The first wall any new entrant faces is the diagnosis rate, not competitors.

In Europe and the US, "one shot every six months" is mainly told as a convenience story. In China the selling point is worth much more, for three reasons.

First, biologic treatment discontinuation rates in China are high, and the main cause is follow-up, not efficacy. Biologics for asthma and nasal polyps require patients to return monthly to a qualified medical institution for injection. With cross-regional care-seeking common and respiratory specialist capacity uneven at the primary level, the monthly return visit is itself a sieve. Reducing the frequency to twice a year frees treatment persistence from the patient's commuting radius.

Second, China's diagnostic funnel is especially long. Seventy percent of asthma patients not correctly diagnosed, fewer than a quarter having had lung function tests — this means the patients who make it to biologics are a minority filtered layer by layer. For these "hard-won" patients, keeping them on treatment is worth more than cutting exacerbations by a few more percent.

Third, ultra-long action reduces not only patient burden but also hospitals' stocking pressure. Twice-yearly dosing means very few turnovers per patient per year, with inventory, cold chain and outpatient injection resource use in hospital pharmacies all significantly lower than for monthly products. Against the backdrop of the widespread difficulty of in-hospital access for biologics in China, this is an underrated access-side advantage.

The reasonable label path is: first lock in maintenance treatment of severe uncontrolled asthma, writing "once every 6 months" directly into dosage and administration as the core differentiator, then expand to nasal polyps and COPD. Asthma is currently the fastest-progressing part in China, and while competitive, the most clearly defined indication.

The reality on the access side is: the TSLP class has not yet entered the NRDL. The same-target tezepelumab is applying for the 2026 list, and its outcome will directly determine the price anchor for this class in China. Within the NRDL, the only biologic currently covering both asthma and nasal polyps is mepolizumab.

This creates a timing problem: Hengrui's China Phase 3 has a primary completion date of January 2028; even if all goes well, the marketing filing will come after 2028. By then the NRDL price band for this class will most likely have been set by the first movers. How much room the latecomer has to negotiate depends on what unique thing it can bring by then — on the current evidence structure, the most likely answer is still dosing frequency, and the adherence and persistence data built around it.