TENX ($TENX) Stock Hub 2026

01 LEVEL Phase 3 misses the primary endpoint: the central TENX thesis has changed

On August 10, 2026, Tenax Therapeutics released topline results from LEVEL, its registrational Phase 3 trial of TNX-103 oral levosimendan in pulmonary hypertension associated with heart failure with preserved ejection fraction, or PH-HFpEF. The study did not meet its primary endpoint of improvement in six-minute walk distance at Week 12 versus placebo. It also failed to show a meaningful advantage on the key secondary endpoint, Kansas City Cardiomyopathy Questionnaire total symptom score.

LEVEL randomized 241 patients across 41 sites in the United States and Canada: 120 to TNX-103 and 121 to placebo. On the prespecified primary analysis, the least-squares mean change in 6MWD was +14.0 meters on TNX-103 versus +10.4 meters on placebo. The treatment difference was therefore only +3.5 meters, with a standard error of 7.3 meters and p=0.63. That is not a near miss; the overall population did not show a statistically persuasive treatment effect on the endpoint around which the registrational study was designed.

The key KCCQ-TSS secondary endpoint was similarly flat: least-squares mean change of +6.6 points on TNX-103 versus +6.5 on placebo, a difference of only +0.1 points. NYHA functional-class improvement and adjudicated clinical worsening also did not separate meaningfully between groups in the topline presentation.

Tenax nevertheless identified a prespecified subgroup with greater baseline disease burden that appeared to benefit. Among the 119 patients who walked less than the trial median of 333 meters at baseline, the least-squares mean treatment difference was +26.3 meters versus placebo, with a 95% confidence interval of 6.0 to 46.7 meters and nominal p=0.0112. Patients aged 71 years and older also showed a prespecified treatment difference of +27.1 meters, while the oldest tertile above age 74 showed +37.6 meters. These findings are clinically interesting, but the company explicitly notes that nominal p-values were not adjusted for multiplicity.

Across the overall population, prespecified exploratory measures also moved in a favorable direction: NT-proBNP was reduced by 49% relative to placebo on the geometric least-squares analysis, with nominal p<0.0001, and right ventricular systolic pressure was reduced by 3.5 mmHg versus placebo, with nominal p=0.0045. Those measures support biological activity, but they were exploratory endpoints and do not establish efficacy after the failed primary endpoint.

02 Status as of August 10, 2026: LEVEL is no longer an open binary — it is a Phase 3 miss with a possible enrichment path

The binary event has resolved negatively on the primary endpoint. The key question for TENX is no longer whether LEVEL succeeds in the overall population; it did not. The new question is whether regulators will accept a revised program focused on patients with greater disease burden and whether the ongoing LEVEL-2 trial can be modified in a way that produces a prospectively testable, registrationally usable result.

Tenax intends to request a Type C meeting with the FDA to review the complete LEVEL dataset and an enrichment strategy. The company also plans parallel scientific consultation with the European Medicines Agency. Management’s August 10 presentation says baseline 6MWD in LEVEL-2 will be capped going forward, while the broader Phase 3 development plan remains open pending regulatory interactions.

Funding and dilution watch: Tenax reported $118.0 million in cash and cash equivalents at June 30, 2026, including $13.4 million of Q2 warrant-exercise proceeds, and guided to runway through Q2 2028. That liquidity is now strategically important because the company may need to redesign or amend late-stage development rather than move directly from a successful LEVEL readout toward a straightforward filing path. The existing pre-funded warrants, ordinary warrants, options and shelf capacity remain relevant to common-equivalent ownership and future financing risk.

03 Executive summary

Tenax Therapeutics is a Phase 3 development-stage biotech focused on cardiopulmonary disease. Its lead asset is TNX-103, an oral formulation of levosimendan being developed for PH-HFpEF. Before August 10, 2026 the equity story was dominated by a clean binary question: could LEVEL reproduce the functional signal seen in earlier work and establish a registrational Phase 3 success? The answer from the overall LEVEL population was no.

LEVEL randomized 241 patients and missed the prespecified primary endpoint. At Week 12, the adjusted difference in six-minute walk distance between TNX-103 and placebo was only +3.5 meters, p=0.63. The key KCCQ-TSS secondary endpoint also failed to separate, with a +0.1-point treatment difference. Those two results materially weaken the prior bull thesis and explain the violent market repricing after the release.

There is still a scientific argument for continued development. The prespecified subgroup of patients with baseline 6MWD below 333 meters showed a +26.3-meter placebo-adjusted benefit, nominal p=0.0112. Older patients also appeared to benefit more. In the overall population, NT-proBNP fell 49% relative to placebo and RVSP improved by 3.5 mmHg, both with strong nominal p-values. TNX-103 also avoided an imbalance in serious adverse events or adjudicated clinical worsening. Those signals suggest biological activity and a possible disease-severity interaction.

But the evidentiary hierarchy matters. The primary endpoint failed. KCCQ-TSS failed. The favorable subgroup and biomarker findings are not equivalent to a positive Phase 3 trial, and the company itself states that the nominal p-values are not adjusted for multiplicity and that the exploratory analyses do not establish efficacy. TENX therefore moves from a “pivotal readout” story to a regulatory salvage and trial-redesign story.

The company plans a Type C meeting with the FDA and parallel EMA consultation. Tenax says the FDA had previously agreed that a single Phase 3 trial with p=0.01 could support an NDA submission, but LEVEL did not deliver that result in the overall population. Management now wants to enrich the study population and cap baseline 6MWD in LEVEL-2. Whether regulators accept that plan, and what prospective evidence they require, becomes the next major value driver.

The balance sheet remains one of the better parts of the story. Tenax reported $118.0 million in cash and cash equivalents at June 30, 2026 and guided to funding through Q2 2028. That cash gives the company room to respond to the setback, but a revised or extended Phase 3 program can consume significant capital and may alter the previously modeled runway.

04 Fast snapshot

05 Current status and latest material updates

The most important update is now the August 10, 2026 LEVEL topline release. The trial failed its primary 6MWD endpoint and key KCCQ-TSS secondary endpoint in the overall population. This supersedes every earlier statement in the hub describing LEVEL as an open binary or an August data window.

The raw primary result was weak: adjusted Week 12 change of +14.0 meters on TNX-103 versus +10.4 meters on placebo, for a +3.5-meter treatment difference and p=0.63. KCCQ-TSS changed by +6.6 versus +6.5, a +0.1-point difference. Those results do not support a broad-population efficacy claim.

The company’s counter-argument is that LEVEL enrolled too many patients with less severe disease. In the prespecified subgroup below the median baseline walk distance of 333 meters, TNX-103 showed a +26.3-meter placebo-adjusted effect. Patients aged 71 and older also showed a +27.1-meter treatment difference. The biomarker package was directionally stronger: NT-proBNP was reduced 49% versus placebo and RVSP by 3.5 mmHg in the overall population.

Safety was mixed but not catastrophic. Serious adverse events were essentially balanced at 10.8% on TNX-103 versus 10.7% on placebo, and adjudicated clinical worsening was 2.5% in both groups. However, overall adverse events were more frequent on TNX-103 at 86.7% versus 71.9%, treatment-related adverse events were 38.3% versus 17.4%, treatment discontinuation due to adverse events was 8.3% versus 1.7%, and dose reduction was 15.0% versus 4.1%. Headache, palpitations and hypotension contributed to the tolerability difference.

The June 2026 Orion supply agreement and sixth license amendment remain in force and still support manufacturing and contractual runway. They do not, however, de-risk the new core issue: whether regulators will allow the program to pivot from a failed all-comers Phase 3 result toward a prospectively enriched severe-disease population.

06 Why TENX matters now

TENX still matters, but for a completely different reason than it did before August 10. The easy catalyst thesis is gone. The stock has moved into the difficult phase that follows a late-stage miss: separating a potentially real pharmacologic signal from a failed registrational endpoint and asking whether a credible regulatory path still exists.

The negative side is straightforward. A Phase 3 primary endpoint with p=0.63 is a decisive failure in the broad enrolled population. The key symptom endpoint did not separate either. The market therefore has to discount the probability, timing and cost of eventual approval more heavily than it did before the readout.

The residual scientific interest comes from internal consistency across disease-severity measures. Patients walking less than 333 meters appeared to benefit, older patients appeared to benefit, and NT-proBNP plus RVSP moved in a favorable direction. Tenax’s presentation also shows the treatment effect declining as baseline exercise capacity increased. That pattern can support an enrichment hypothesis, but it now has to survive regulatory scrutiny and prospective confirmation.

This makes the FDA Type C meeting and the design of LEVEL-2 far more important than ordinary conference-calendar noise. If regulators agree that a prospectively defined higher-disease-burden population is a reasonable path forward, the story retains late-stage optionality. If they demand a new confirmatory trial, broader replication, or do not accept the enrichment logic, development time and capital requirements can rise materially.

07 Company overview

Tenax Therapeutics is headquartered in Chapel Hill, North Carolina. The company describes itself as a Phase 3, development-stage pharmaceutical company using clinical insights to develop novel cardiopulmonary therapies. The current corporate identity is built almost entirely around levosimendan, with TNX-103 as the practical lead program.

Levosimendan is not a brand-new molecule. It has a long history in acute cardiac care outside the United States, where intravenous levosimendan has been authorized in many countries for hospitalized patients with acutely decompensated heart failure. Tenax’s strategy is different: the company is attempting to develop an oral formulation for chronic use in PH-HFpEF, a disease state where existing treatment options do not directly solve the pulmonary vascular and venous congestion problem that defines the condition.

This gives TENX a somewhat unusual profile. It is not a typical early-stage platform biotech selling investors on a broad discovery engine. It is also not a commercial-stage biotech with diversified revenue. It is a focused clinical execution story built around repurposing, reformulating and clinically validating a known pharmacologic mechanism in a disease where the unmet need is large and the regulatory evidence base is limited.

Pipeline snapshot

The key point is simple: investors should not treat Tenax as a diversified biotech pipeline. The current stock thesis is overwhelmingly dependent on the levosimendan PH-HFpEF program. That concentration can create upside if data are strong, but it also means the downside from weak data is not buffered by multiple independent late-stage assets.

08 The disease: PH-HFpEF

PH-HFpEF stands for pulmonary hypertension associated with heart failure with preserved ejection fraction. In plain English, this is a condition where patients have heart failure symptoms even though the heart’s pumping fraction is preserved, while pressure backs up into the pulmonary circulation. Patients may experience shortness of breath, exercise intolerance, congestion, reduced functional capacity and repeated clinical worsening events.

The disease is difficult because it sits between cardiology and pulmonary vascular medicine. It is not classic pulmonary arterial hypertension. It is related to left-sided heart disease and abnormal filling pressures. That matters because drugs that work in pulmonary arterial hypertension cannot simply be assumed to work in PH-HFpEF. The history of pulmonary hypertension associated with left heart disease includes several failed or mixed attempts to apply pulmonary vasodilator logic to a more complex hemodynamic problem.

Tenax’s thesis is that levosimendan may work through a different angle. Rather than only thinking about pulmonary arterial vasodilation, the company emphasizes venous tone, splanchnic circulation, volume distribution, pulmonary pressures and exercise hemodynamics. The biological idea is that reducing excessive stressed blood volume and improving hemodynamic efficiency may allow patients to walk farther and tolerate exertion better.

Clinical translation after LEVEL: the mechanism showed biomarker and hemodynamic activity, but the broad Phase 3 population did not show a statistically significant 6MWD benefit. The development thesis now depends on whether disease severity truly identifies a responsive population and whether that hypothesis can be prospectively confirmed.

09 TNX-103 after LEVEL: biological activity without broad-population Phase 3 efficacy

TNX-103 is Tenax’s oral formulation of levosimendan. Mechanistically, levosimendan is generally described as a calcium sensitizer and potassium-ATP channel activator. Tenax’s cardiopulmonary thesis is that the drug can influence venous tone, volume distribution, pulmonary pressures and cardiac loading conditions in PH-HFpEF.

LEVEL provides a more complicated answer than either “the drug works” or “the drug does nothing.” The overall 6MWD endpoint failed, so TNX-103 did not demonstrate broad-population Phase 3 efficacy as designed. At the same time, the strong NT-proBNP and RVSP changes indicate that the oral formulation was pharmacologically active, and the prespecified severe-disease subgroup suggests that activity may translate into functional benefit in a narrower patient population.

The dosing strategy also appears to have produced meaningful systemic exposure, but tolerability cannot be ignored. Any adverse event, treatment-related adverse events, dose reductions and discontinuations were all more frequent on TNX-103 than on placebo. For a chronic therapy, the final benefit-risk profile will have to justify that burden in the population most likely to benefit.

What TNX-103 now has to prove

• Prospective efficacy: reproduce a clinically meaningful 6MWD benefit in a prospectively defined higher-disease-burden population rather than relying on the failed all-comers LEVEL result.
• Subgroup validity: demonstrate that baseline 6MWD or another disease-severity marker consistently identifies responders across an independent or prospectively enriched dataset.
• Biomarker-to-clinical linkage: show that favorable NT-proBNP and RVSP effects translate into functional or clinical benefit that regulators and physicians can use.
• Tolerability: manage headache, palpitations, hypotension, dose reductions and discontinuations sufficiently for chronic use.
• Regulatory usability: generate evidence that the FDA and EMA accept as part of a coherent submission strategy after the failed LEVEL primary endpoint.

10 The HELP trial: supportive, but not definitive

The earlier HELP trial is the reason TENX is credible enough to attract attention before the Phase 3 data. In HELP, levosimendan treatment produced a 29.3-meter improvement in six-minute walk distance compared with placebo, with a reported p-value of 0.033. That is an important signal because six-minute walk distance is the same functional domain being tested in the Phase 3 program.

Still, the HELP trial should not be oversold. It was small. It used intravenous levosimendan. It did not significantly reduce the original primary endpoint of exercise pulmonary capillary wedge pressure at six weeks. The positive part of the study was the broader hemodynamic and functional signal, especially the 6MWD improvement. For investors, HELP is best understood as a mechanistic and clinical signal strong enough to justify Phase 3, not as proof that LEVEL will succeed.

This nuance became decisive on August 10. HELP was strong enough to justify Phase 3, but LEVEL did not reproduce a meaningful overall-population treatment effect on 6MWD. The remaining argument is narrower: the HELP-like signal may have been concentrated in patients with greater disease burden, a hypothesis that now requires prospective validation rather than retrospective optimism.

11 The Phase 3 program after LEVEL: LEVEL-2 becomes the key salvage vehicle

Tenax built its registrational strategy around two Phase 3 studies, LEVEL and LEVEL-2. LEVEL has now produced a failed primary-endpoint result in the overall population. That fundamentally changes the role of LEVEL-2: instead of simply confirming a successful first pivotal study, it may need to prospectively test the disease-severity hypothesis generated by LEVEL and provide the evidence regulators would require for any future filing.

LEVEL — completed, primary endpoint missed

LEVEL randomized 241 patients across 41 U.S. and Canadian sites. Patients received TNX-103 1 mg twice daily, titrated to 1 mg three times daily beginning at Week 5 as tolerated, or placebo. The primary endpoint was change in 6MWD at Week 12. The adjusted treatment difference was +3.5 meters, p=0.63. The key KCCQ-TSS endpoint also failed to separate.

The trial nevertheless generated prespecified subgroup evidence suggesting stronger response with greater disease burden. Below the 333-meter median baseline 6MWD, the placebo-adjusted treatment effect was +26.3 meters. The company also reported stronger effects in older patients and favorable exploratory NT-proBNP and RVSP changes. These findings are the basis for the proposed enrichment strategy.

LEVEL-2 — ongoing, but the design strategy is changing

LEVEL-2 is the global Phase 3 study of TNX-103 with a 26-week treatment duration. Before the LEVEL readout, it was positioned as the second registrational study providing broader efficacy and safety exposure. On August 10, management said baseline 6MWD in LEVEL-2 will be capped moving forward and that the overall Phase 3 development plan will be modified after discussions with the FDA and EMA.

This is a crucial distinction. A protocol adjustment made prospectively can be scientifically and regulatorily meaningful, but the exact cutoff, statistical plan, enrollment impact, sample size, handling of patients already enrolled and regulatory acceptability have not yet been established publicly. Investors should not assume the 333-meter median observed in LEVEL automatically becomes the final LEVEL-2 criterion.

12 The August 10, 2026 update: what the LEVEL result actually says

The August 10 release is the single most important event in the current TENX file. The trial missed the endpoint that mattered most. The correct starting point is therefore the overall randomized population, not the favorable subgroup.

In the prespecified subgroup with baseline 6MWD below 333 meters, the treatment difference was +26.3 meters, 95% CI 6.0 to 46.7, nominal p=0.0112. By contrast, patients above 333 meters showed a negative treatment difference in the company’s analysis. A post hoc quartile analysis showed the effect declining as baseline walking capacity increased, from +32.4 meters in the lowest quartile to -27.3 meters in the highest quartile.

The biomarker package is the strongest part of the positive read-through. NT-proBNP in the overall population showed a geometric least-squares mean ratio of 0.51 versus placebo, corresponding to a 49% reduction, nominal p<0.0001. RVSP fell by 3.5 mmHg versus placebo, nominal p=0.0045. Tenax and the LEVEL investigators argue these data demonstrate biological activity and support the disease-severity enrichment hypothesis.

Safety did not reveal a new major signal, but tolerability was clearly worse on active drug. Any adverse event occurred in 86.7% on TNX-103 versus 71.9% on placebo; treatment-related adverse events in 38.3% versus 17.4%; discontinuation due to adverse events in 8.3% versus 1.7%; and dose reduction in 15.0% versus 4.1%. Serious adverse events were balanced.

13 What LEVEL showed — and what it did not prove

The cleanest way to interpret LEVEL is to separate confirmed facts from hypotheses that require another prospective test.

The most defensible positive interpretation is that TNX-103 may have a real effect in a sicker PH-HFpEF subgroup and clearly produces measurable biological changes. The most defensible negative interpretation is that the drug failed to demonstrate efficacy in the population Tenax chose for its registrational trial. Both can be true at the same time.

What LEVEL does not prove is that selecting patients below 333 meters will automatically produce a positive future Phase 3. The 333-meter threshold emerged as the trial median, and the exact enrichment criterion for LEVEL-2 still has to be agreed prospectively. Replication risk remains high.

14 Regulatory path: from expected de-risking to FDA/EMA renegotiation

Before the LEVEL result, the regulatory discussion centered on how a successful first registrational study would combine with LEVEL-2 and the long-term safety database. After August 10, the regulatory problem is more fundamental: Tenax must convince regulators that the failed overall-population trial still identifies a scientifically credible population in which TNX-103 can be prospectively tested.

Tenax intends to request a Type C meeting with the FDA and seek parallel scientific consultation from the EMA. Management says it will present the full LEVEL dataset, recommend an enrichment strategy and discuss modifications to the ongoing registrational development plan. The company has also stated that the FDA had previously agreed that a single Phase 3 trial achieving p=0.01 could be sufficient for an NDA submission in PH-HFpEF. That prior agreement is relevant context, but it does not rescue LEVEL because the primary endpoint in LEVEL was p=0.63.

The key regulatory questions now include the acceptable baseline 6MWD cap, whether LEVEL-2 can be amended without compromising interpretability, whether already-enrolled patients affect the analysis population, whether a new or additional confirmatory trial is needed, how the multiplicity issue around subgroup findings will be handled, and what total safety exposure is required.

The August 29 ESC presentation is therefore more than a conference follow-up. It will give cardiologists and investors the first fuller look at whether the disease-severity interaction appears clinically coherent across baseline characteristics, biomarkers, echocardiography, safety and functional outcomes.

15 Financial position

Tenax entered the LEVEL readout with a much stronger cash position than many clinical-stage biotech peers. In its July 31 Q2 report, the company disclosed $118.0 million in cash and cash equivalents at June 30, 2026. Q2 warrant exercises provided approximately $13.4 million, and management extended expected funding through the second quarter of 2028. After the August 10 miss, that liquidity becomes a cushion for regulatory work and potential trial redesign rather than merely a bridge through a successful catalyst.

Operating expenses are rising because the company is advancing two Phase 3 studies. Q2 2026 R&D expense was $12.9 million, up from $6.1 million a year earlier; G&A expense was $5.9 million versus $5.7 million; and net loss widened to $17.8 million from $10.9 million. The Q2 filing also reported 31,949,785 common shares outstanding at June 30 versus 9,314,130 at year-end 2025. Weighted-average shares used for the quarter, including pre-funded warrants, were 50,869,259, illustrating why economic exposure cannot be inferred from basic common shares alone.

The reported cash runway still reduces immediate solvency pressure, but the quality of that runway must now be reassessed against a potentially longer development path. A protocol amendment, slower enrollment in a more selective population, additional regulatory interactions or a new confirmatory study can change burn assumptions. The pre-readout runway guidance should therefore not be interpreted as proof that the existing cash fully funds whatever revised program regulators may require.

16 Capital structure and dilution risk

The biggest trap in reading TENX quickly is looking only at basic shares outstanding. Tenax has common shares outstanding, pre-funded warrants, ordinary warrants and employee/director options. For a biotech with this kind of financing history, common-equivalent analysis is essential.

As of March 31, 2026, Tenax reported 24,275,500 common shares issued and outstanding. It also reported 24,566,607 pre-funded warrants outstanding with a $0.01 weighted-average exercise price. Because pre-funded warrants are effectively near-common equity once exercised, they should be considered when thinking about economic ownership and market capitalization on a fully converted basis.

The company also reported 10,472,699 ordinary warrants outstanding with a weighted-average exercise price of $6.23, and 7,874,932 options outstanding with a weighted-average exercise price of $7.34. At stock prices above those averages, a large portion of this overhang is economically relevant, although exact exercise behavior depends on holder decisions, contractual details and market conditions.

Important distinction: the table below is not a GAAP diluted share count. It is a practical investor map of potential common-equivalent overhang based on the company’s March 31, 2026 SEC filing.

This is not automatically negative. Warrant exercises helped improve the cash position in Q1 2026. The company received $30.5 million from the exercise of warrants and pre-funded warrants during the quarter. That is the dual nature of biotech dilution: it expands the share base, but it can also strengthen the balance sheet and reduce going-concern pressure. For TENX, the cash runway improvement is real, but investors still need to model ownership on a broader base than basic shares alone.

17 Who bought after the crash, and at what price

The eighteen days after the LEVEL miss produced more ownership filings than the previous six months. They are not all the same kind of document, and reading them as one wave would be wrong.

The routine filings that describe the world before the crash

Seven Schedule 13G amendments were filed between August 12 and August 14, and every one of them carries an event date of June 30, 2026. These are the quarterly updates due within forty-five days of quarter end, so they photograph the register as it stood six weeks before the trial result. They say nothing about anyone’s reaction to it. Three of them — Perceptive, Venrock and Ikarian — carry the flag for a holding at or below five per cent, which means they are exit amendments: the holder has fallen under the reporting threshold and will not have to file again.

The three that arrived after

Three new Schedule 13Gs carry event dates from the days after the result, which is when the reporting obligation was triggered. All three were filed under Rule 13d-1(c), the passive-investor route.

All three measure their percentage against the 37,423,917 shares outstanding at July 28, 2026 disclosed in the Form 10-Q filed on July 31. A Schedule 13G says a threshold was crossed; it does not say at what price, and none of the three publishes an average.

ADAR1 crossed ten per cent, and the Form 4 gives the prices

The filing that says the most is not a 13G. ADAR1 Capital Management, LLC and its sole manager Daniel Schneeberger filed a Form 3 on August 24, 2026 with an event date of August 20, declaring themselves a ten per cent owner, which is what triggers Section 16 reporting. The initial statement shows 3,827,951 common shares held indirectly through private funds, plus pre-funded warrants over 59,073 shares at a $0.01 exercise price and warrants over 31,096 shares at $4.50, both dated August 8, 2024.

A Form 4 filed the same day as the third purchase records what happened next, all of it open-market buying under transaction code P:

Merlintrader arithmetic, not a disclosed total: the three purchases are 1,025,867 shares for $1,814,147, at a volume-weighted average of $1.7684. The three reported prices are themselves weighted averages of multiple trades, in ranges the footnotes give as $1.7650 to $1.8000, $1.7250 to $1.8000 and $1.7000 to $1.8000, so the total is exact on the reported inputs and approximate on the underlying fills. The closing holding of 4,853,818 shares is about 12.97 per cent of the 37,423,917 shares outstanding at July 28. Both figures are calculated from the filings; neither appears in them.

What this does and does not tell you. It tells you that a fund manager with access to the same public data as everyone else was willing to buy more than a million shares at around $1.77 in the two weeks after a Phase 3 failure, and to cross a threshold that carries reporting obligations and a short-swing profit rule rather than stay below it. It does not tell you why, and the filings give no reason. The scale matters too: $1.81 million is a small position in absolute terms, and the whole company was worth less than $70 million in those days.

Primary sources: ADAR1 Form 3, event date August 20, 2026, filed August 24 · ADAR1 Form 4 of August 24, 2026 · All Tenax Schedule 13 filings on EDGAR

18 Intellectual property, Orion license and manufacturing supply

Tenax’s levosimendan strategy depends on both patent protection and its license relationship with Orion Corporation. According to Tenax’s SEC filings, the company has license rights connected to levosimendan formulations and has expanded its rights over time, including rights related to oral levosimendan and other formulations for PH-HFpEF.

The Orion relationship also includes economics. Tenax’s filings describe regulatory and commercial milestone obligations, including a $10.0 million milestone due to Orion upon FDA approval of a levosimendan-based product, as well as other potential commercial milestones and royalties based on sales. These obligations are normal in licensed-drug development, but they should be included in any long-term modeling of economics if the program succeeds.

The June 2026 supply agreement is strategically relevant because it gives more structure to the manufacturing side of the oral levosimendan program. Orion will act as the primary supplier of orally administered levosimendan product for development and, if approved, commercial purposes. The agreement includes operational terms around forecasting, ordering, delivery, quality, pricing, non-conforming product provisions and certain alternative manufacturing rights. It also includes cost-sharing provisions related to scaling up Orion’s manufacturing capabilities.

The sixth amendment to the license agreement extends the U.S. regulatory approval milestone deadline to December 31, 2035. In practical terms, this gives Tenax more contractual runway around the levosimendan program. It should not be treated as clinical validation, but it is relevant to the asset’s long-term control and development flexibility.

19 Management and execution

Biotech catalyst stories often focus so heavily on the molecule that they ignore execution. In TENX, execution matters because the company is trying to run a global late-stage cardiopulmonary program with a small-company infrastructure. Enrollment, site activation, database lock, statistical analysis, safety monitoring, manufacturing planning and future regulatory interaction all require discipline.

The company made commercial and financial leadership additions ahead of the data and regulatory transition, including Thomas R. Staab as Chief Financial Officer in April 2026 and Timothy Healey as Chief Commercial Officer in May 2026. The LEVEL miss changes the near-term priority: regulatory strategy, protocol redesign and cost discipline now matter more than launch-readiness planning.

The most important execution checkpoint is now how transparently management handles the failed primary endpoint and how quickly it converts the subgroup hypothesis into a regulator-reviewed prospective plan. The late-breaking ESC slot increases visibility, but it also increases scrutiny: investors and clinicians will be looking for the full distribution of outcomes, subgroup consistency, missing-data handling, tolerability detail and evidence that the enrichment thesis is more than a convenient post-miss narrative.

20 Analyst coverage and retail sentiment after the LEVEL miss

Analyst targets published before August 10 should be treated as stale until firms explicitly re-underwrite the company using the failed primary endpoint, the severe-disease subgroup signal, the regulatory redesign risk and the new implied timeline. A pre-readout target based on a successful LEVEL probability is not directly comparable with the post-readout equity case.

The immediate market verdict was severe. Reuters reported that TENX shares fell more than 85% in premarket trading after the company disclosed the Phase 3 miss. That reaction is consistent with the structure of the prior thesis: the company is heavily dependent on TNX-103 and LEVEL was the dominant near-term value event.

Retail sentiment data collected on August 9 are now explicitly pre-readout data. They are useful as a record of positioning before the event, not as a description of current sentiment. Any post-readout reading is likely to be dramatically different and should not be inferred from the August 9 snapshot.

21 Bull case after the miss

The bull case is no longer that LEVEL was successful. It was not. The remaining bull thesis is a salvage thesis built on the possibility that Tenax enrolled too broad a PH-HFpEF population and that TNX-103 has clinically meaningful activity in patients with greater disease burden.

The strongest evidence for that view is the prespecified subgroup below 333 meters baseline 6MWD, where the placebo-adjusted effect was +26.3 meters with nominal p=0.0112. The age analyses point in the same direction, and the NT-proBNP plus RVSP findings provide an independent biological signal across the overall population. If those relationships remain coherent in the full dataset and regulators agree on a prospective enrichment strategy, LEVEL may still have identified a viable target population even though it failed as designed.

The balance sheet gives Tenax time to pursue that strategy. With $118.0 million in cash and cash equivalents at June 30 and runway guidance through Q2 2028, the company is not immediately forced into a distressed financing simply to survive the readout. The ongoing LEVEL-2 infrastructure may also provide a faster route to testing the enrichment hypothesis than starting from zero, depending on regulatory feedback.

The most constructive scenario would be an FDA/EMA-aligned protocol amendment that prospectively limits enrollment to higher-disease-burden patients, preserves enough statistical integrity to support a future submission, and produces a confirmatory treatment effect consistent with the +26-meter LEVEL subgroup signal. That would not erase the failed first study, but it could restore a credible late-stage path.

22 Bear case: the core risk has already materialized

The principal pre-readout bear case was that TNX-103 would fail to reproduce the HELP signal in a larger oral Phase 3 study. That risk has materialized in the overall LEVEL population. The primary endpoint missed decisively and the key symptom endpoint did not separate.

The next bear argument is statistical and regulatory. Subgroup findings can be real, but they can also overstate treatment effects, especially when many analyses are examined after an unsuccessful primary endpoint. Tenax says the below-333-meter and age analyses were prespecified, which improves their credibility, but the p-values are nominal and not adjusted for multiplicity. Regulators may demand robust prospective confirmation before giving those results meaningful weight.

The third bear argument is that LEVEL-2 may become longer, more expensive or less straightforward. Enriching enrollment can reduce the available patient pool. Protocol changes may require additional operational work. Regulators could ask for another confirmatory trial. Any of those outcomes can increase burn and push a potential filing farther out.

The fourth bear argument is commercial. Even if a narrower high-disease-burden indication eventually succeeds, the addressable population may be smaller than models built around a broad PH-HFpEF label. Tolerability also deserves attention because treatment-related adverse events, dose reductions and discontinuations were meaningfully higher on TNX-103.

Finally, TENX remains concentrated around levosimendan. The market’s more-than-85% premarket decline after the release demonstrates how little diversification investors assign to the rest of the portfolio when the lead program is impaired.

23 Post-LEVEL scenario map

24 Key red flags

• Phase 3 primary endpoint failure: LEVEL missed 6MWD with a +3.5-meter treatment difference and p=0.63.
• Key secondary endpoint failure: KCCQ-TSS showed essentially no separation between TNX-103 and placebo.
• Subgroup dependence: the remaining efficacy thesis depends heavily on patients with greater baseline disease burden.
• Multiplicity: favorable subgroup and exploratory p-values are nominal and not adjusted for multiplicity; Tenax states these analyses do not establish efficacy.
• Protocol-redesign risk: LEVEL-2 is ongoing, but the final enrichment cutoff and statistical framework are not yet regulator-endorsed publicly.
• Tolerability: treatment-related AEs, dose reductions and discontinuations were higher on TNX-103 despite balanced serious AEs.
• Timeline risk: regulatory discussions or additional confirmatory requirements can materially delay any potential filing.
• Runway risk after redesign: pre-readout guidance through Q2 2028 may change if the program becomes longer or more expensive.
• Capital-structure complexity: pre-funded warrants, ordinary warrants, options and shelf capacity remain material to common-equivalent ownership.
• Single-asset dependence: TNX-103 remains the dominant value driver; the market reaction shows the sensitivity of the equity to this program.

25 What can make TENX more interesting again?

The path back to a stronger thesis now requires evidence, not narrative. The first step is regulatory clarity. Tenax needs to show that the FDA and EMA view a prospectively enriched high-disease-burden population as a legitimate development strategy rather than an attempt to rescue a failed trial through subgroup selection.

The second step is a transparent LEVEL-2 amendment. Investors need the exact baseline 6MWD cap, sample-size implications, handling of patients already enrolled, statistical hierarchy, endpoint plan and revised timeline. A vague statement that the trial will be “enriched” is not enough to model approval probability or cash needs.

The third step is replication. The +26.3-meter treatment difference below 333 meters is meaningful enough to justify attention, but it needs to recur prospectively. The strongest recovery case would pair a replicated functional benefit with the same direction of NT-proBNP, RVSP and safety findings seen in LEVEL.

The fourth step is financial discipline. A longer development program can consume the current balance sheet faster than pre-readout runway guidance implied. Management will need to show that any revised plan is fundable without destroying the remaining common-equity value.

Sentiment note: the Stocktwits snapshot below was taken on August 9, 2026, before the LEVEL result. It is preserved as a record of pre-event positioning and should not be read as current post-miss sentiment.

26 Bottom line

The TENX story changed materially on August 10, 2026. LEVEL did not meet its primary 6MWD endpoint and did not show a meaningful benefit on the key KCCQ-TSS secondary endpoint. The adjusted treatment difference on 6MWD was only +3.5 meters with p=0.63. For an equity thesis built around a near-term registrational readout, that is a major failure and it must be described plainly.

There is still a development argument, but it is narrower and more uncertain. The prespecified subgroup below 333 meters baseline 6MWD showed a +26.3-meter placebo-adjusted benefit, older patients appeared to respond more strongly, and NT-proBNP plus RVSP improved in the overall population. Serious adverse events were balanced. Those findings justify further investigation and give Tenax a scientifically coherent reason to seek an enriched Phase 3 strategy.

They do not erase the pivotal miss. The favorable p-values are nominal, multiplicity remains relevant, the exact LEVEL-2 redesign is not yet regulator-endorsed publicly, and tolerability was worse on active drug. The company now plans a Type C meeting with the FDA, parallel EMA consultation, an enriched LEVEL-2 approach and a full scientific presentation at ESC on August 29.

The balance sheet gives Tenax room to pursue that path, with $118.0 million in cash and cash equivalents reported at June 30 and management’s pre-readout runway guidance through Q2 2028. But a longer or redesigned registrational program can change that math. Cash is now a strategic asset that buys time to attempt a rescue; it is not evidence that the clinical problem has been solved.

For Merlintrader readers, TENX should now be framed as a post-Phase-3-miss regulatory salvage story. The next decisive questions are whether regulators accept an enriched disease-severity population, how LEVEL-2 is amended, whether the +26-meter subgroup effect can be reproduced prospectively, and how much time and capital that path requires.