Biotechnology Value Fund and related entities, including BVF Partners and Mark N. Lampert, report beneficial ownership of 768,200 shares of Tenax Therapeutics common stock, representing approximately 9.99% of the outstanding shares as of December 31, 2025.
The group holds a mix of common shares and pre-funded warrants, with only 428,651 of 10,099,974 underlying pre-funded warrant shares currently counted due to a 9.99% ownership blocker. They also hold 5,209,174 additional warrants that are immediately exercisable in principle but not currently exercisable because of similar 9.99% ownership limits.
The filing clarifies how various BVF funds, their general partners, BVF Inc. and Mr. Lampert may be deemed to share voting and dispositive power, while several entities formally disclaim beneficial ownership of securities held by affiliated funds or accounts. The group certifies the holdings are not for the purpose of changing or influencing control of Tenax.
Positive
None.
Negative
None.
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
UNDER THE SECURITIES EXCHANGE ACT OF 1934
(Amendment No. 1)
TENAX THERAPEUTICS, INC.
(Name of Issuer)
Common Stock, $0.0001 par value per share
(Title of Class of Securities)
88032L605
(CUSIP Number)
12/31/2025
(Date of Event Which Requires Filing of this Statement)
Check the appropriate box to designate the rule pursuant to which this Schedule is filed:
Rule 13d-1(b)
Rule 13d-1(c)
Rule 13d-1(d)
SCHEDULE 13G
CUSIP No.
88032L605
1
Names of Reporting Persons
BIOTECHNOLOGY VALUE FUND L P
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
596,433.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
596,433.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
596,433.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
7.8 %
12
Type of Reporting Person (See Instructions)
PN
SCHEDULE 13G
CUSIP No.
88032L605
1
Names of Reporting Persons
BVF I GP LLC
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
596,433.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
596,433.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
596,433.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
7.8 %
12
Type of Reporting Person (See Instructions)
OO
SCHEDULE 13G
CUSIP No.
88032L605
1
Names of Reporting Persons
BIOTECHNOLOGY VALUE FUND II LP
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
165,382.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
165,382.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
165,382.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
2.3 %
12
Type of Reporting Person (See Instructions)
PN
SCHEDULE 13G
CUSIP No.
88032L605
1
Names of Reporting Persons
BVF II GP LLC
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
165,382.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
165,382.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
165,382.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
2.3 %
12
Type of Reporting Person (See Instructions)
OO
SCHEDULE 13G
CUSIP No.
88032L605
1
Names of Reporting Persons
Biotechnology Value Trading Fund OS LP
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
CAYMAN ISLANDS
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
0.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
0.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
0.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
0 %
12
Type of Reporting Person (See Instructions)
PN
SCHEDULE 13G
CUSIP No.
88032L605
1
Names of Reporting Persons
BVF Partners OS Ltd.
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
CAYMAN ISLANDS
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
0.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
0.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
0.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
0 %
12
Type of Reporting Person (See Instructions)
CO
SCHEDULE 13G
CUSIP No.
88032L605
1
Names of Reporting Persons
BVF GP HOLDINGS LLC
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
761,815.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
761,815.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
761,815.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
9.9 %
12
Type of Reporting Person (See Instructions)
OO
SCHEDULE 13G
CUSIP No.
88032L605
1
Names of Reporting Persons
BVF PARTNERS L P/IL
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
768,200.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
768,200.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
768,200.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
9.99 %
12
Type of Reporting Person (See Instructions)
IA, PN
SCHEDULE 13G
CUSIP No.
88032L605
1
Names of Reporting Persons
BVF INC/IL
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
768,200.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
768,200.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
768,200.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
9.99 %
12
Type of Reporting Person (See Instructions)
CO
SCHEDULE 13G
CUSIP No.
88032L605
1
Names of Reporting Persons
LAMPERT MARK N
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
UNITED STATES
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
768,200.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
768,200.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
768,200.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
9.99 %
12
Type of Reporting Person (See Instructions)
IN
SCHEDULE 13G
Item 1.
(a)
Name of issuer:
TENAX THERAPEUTICS, INC.
(b)
Address of issuer's principal executive offices:
Item 2.
(a)
Name of person filing:
Biotechnology Value Fund, L.P. ("BVF")
BVF I GP LLC ("BVF GP")
Biotechnology Value Fund II, L.P. ("BVF2")
BVF II GP LLC ("BVF2 GP")
Biotechnology Value Trading Fund OS LP ("Trading Fund OS")
BVF Partners OS Ltd. ("Partners OS")
BVF GP Holdings LLC ("BVF GPH")
BVF Partners L.P. ("Partners")
BVF Inc.
Mark N. Lampert ("Mr. Lampert")
Each of the foregoing is referred to as a "Reporting Person" and collectively as the "Reporting Persons."
(b)
Address or principal business office or, if none, residence:
Biotechnology Value Fund, L.P.
44 Montgomery St., 40th Floor
San Francisco, California 94104
BVF I GP LLC
44 Montgomery St., 40th Floor
San Francisco, California 94104
Biotechnology Value Fund II, L.P.
44 Montgomery St., 40th Floor
San Francisco, California 94104
BVF II GP LLC
44 Montgomery St., 40th Floor
San Francisco, California 94104
Biotechnology Value Trading Fund OS LP
PO Box 309 Ugland House
Grand Cayman, KY1-1104
Cayman Islands
BVF Partners OS Ltd.
PO Box 309 Ugland House
Grand Cayman, KY1-1104
Cayman Islands
BVF GP Holdings LLC
44 Montgomery St., 40th Floor
San Francisco, California 94104
BVF Partners L.P.
44 Montgomery St., 40th Floor
San Francisco, California 94104
BVF Inc.
44 Montgomery St., 40th Floor
San Francisco, California 94104
Mark N. Lampert
44 Montgomery St., 40th Floor
San Francisco, California 94104
(c)
Citizenship:
Biotechnology Value Fund, L.P.
Delaware
BVF I GP LLC
Delaware
Biotechnology Value Fund II, L.P.
Delaware
BVF II GP LLC
Delaware
Biotechnology Value Trading Fund OS LP
Cayman Islands
BVF Partners OS Ltd.
Cayman Islands
BVF GP Holdings LLC
Delaware
BVF Partners L.P.
Delaware
BVF Inc.
Delaware
Mark N. Lampert
United States
(d)
Title of class of securities:
Common Stock, $0.0001 par value per share
(e)
CUSIP No.:
88032L605
Item 3.
If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
(a)
Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
(b)
Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
(c)
Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
(d)
Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
(e)
An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);
(f)
An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);
(g)
A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);
(h)
A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
(i)
A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
(j)
A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J). If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J),
please specify the type of institution:
(k)
Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
Item 4.
Ownership
(a)
Amount beneficially owned:
As of the close of business on December 31, 2025, the Reporting Persons and a certain Partners managed account (the "Partners Managed Account") held certain pre-funded warrants (the "Pre-Funded Warrants") exercisable for an aggregate of 10,099,974 shares of the Issuer's Common Stock, $0.0001 par value per share (the "Shares"). Each Pre-Funded Warrant is exercisable for one Share at an exercise price of $0.01 per Share. The Pre-Funded Warrants are immediately exercisable and have no expiration date. The exercise of the Pre-Funded Warrants is subject to the limitations of the Pre-Funded Warrants Blocker (as defined and described below). The Pre-Funded Warrants provide that a holder of Pre-Funded Warrants will not have the right to exercise any portion of its Pre-Funded Warrants if such holder, together with its Attribution Parties (as defined in the Form of Prefunded Warrant to Purchase Common Stock, which is attached as Exhibit 4.1 to the Issuer's Current Report on Form 8-K filed with the Securities and Exchange Commission on August 6, 2024 (the "August 2024 8-K")), would beneficially own in excess of 9.99% of the number of Shares outstanding immediately after giving effect to such exercise (the "Pre-Funded Warrants Blocker"). As of December 31, 2025, the Pre-Funded Warrants Blocker limits the exercise of the Pre-Funded Warrants by the Reporting Persons and the Partners Managed Account to 428,651 out of 10,099,974 Shares underlying the Pre-Funded Warrants held by them.
As of the close of business on December 31, 2025, the Reporting Persons and the Partners Managed Account also held an aggregate of 5,209,174 warrants (the "Warrants"). The Warrants can be exercised at any time after their original issuance for Shares, or in lieu thereof, additional Pre-Funded Warrants. The Warrants are immediately exercisable and expire at the earlier of (i) 30 trading days following the date of the Issuer's initial public announcement of topline data from its Phase 3 LEVEL trial (the "Topline Data Announcement"), (ii) immediately upon the exercise of the Pre-Funded Warrants if such exercise is prior to the Topline Data Announcement, provided that if the Pre-Funded Warrant is not exercised in full, the Warrant expires proportionally to the extent the Pre-Funded Warrant is exercised, and (iii) August 8, 2029. The Warrants provide that a holder of Warrants will not have the right to exercise any portion of its Warrants if such holder, together with its Attribution Parties (as defined in the Form of Warrant to Purchase Common Stock or Pre-Funded Warrants, which is attached as Exhibit 4.2 to the August 2024 8-K), would beneficially own in excess of 9.99% of the number of Shares outstanding immediately after giving effect to such exercise (the "Warrants Blocker"). If the holder is not permitted to exercise a Warrant for Shares due to the foregoing limitation, then the holder may exercise the Warrant for an equivalent number of Pre-Funded Warrants with an exercise price of $0.01 as long as the Pre-Funded Warrants Blocker is equivalent to the Warrants Blocker. As of December 31, 2025, none of the Warrants held by the Reporting Persons are exercisable due to the Warrants Blocker.
As of the close of business on December 31, 2025 (i) BVF beneficially owned 596,433 Shares, including 428,651 Shares underlying certain Pre-Funded Warrants held by it and excluding (a) 5,052,505 Shares underlying certain Pre-Funded Warrants and (b) 2,826,968 Shares underlying the Warrants held by it; (ii) BVF2 beneficially owned 165,382 Shares, excluding (a) 3,998,570 Shares underlying the Pre-Funded Warrants and (b) 2,062,307 Shares underlying the Warrants held by it; and (iii) Trading Fund OS beneficially owned zero Shares, excluding (a) 466,213 Shares underlying the Pre-Funded Warrants and (b) 240,455 Shares underlying the Warrants held by it.
BVF GP, as the general partner of BVF, may be deemed to beneficially own the 596,433 Shares beneficially owned by BVF.
BVF2 GP, as the general partner of BVF2, may be deemed to beneficially own the 165,382 Shares beneficially owned by BVF2.
Partners, as the general partner of Trading Fund OS, may be deemed to beneficially own zero Shares.
BVF GPH, as the sole member of each of BVF GP and BVF2 GP, may be deemed to beneficially own the 761,815 Shares beneficially owned in the aggregate by BVF and BVF2.
Partners, as the investment manager of BVF, BVF2 and Trading Fund OS, and the sole member of Partners OS, may be deemed to beneficially own the 768,200 Shares beneficially owned in the aggregate by BVF, BVF2 and Trading Fund OS and held in the Partners Managed Account, including 6,385 Shares held in the Partners Managed Account, which excludes (a) 154,035 Shares underlying the Pre-Funded Warrants and (b) 79,444 Shares underlying the Warrants held in the Partners Managed Account.
BVF Inc., as the general partner of Partners, may be deemed to beneficially own the 768,200 Shares beneficially owned by Partners.
Mr. Lampert, as a director and officer of BVF Inc., may be deemed to beneficially own the 768,200 Shares beneficially owned by BVF Inc.
The foregoing should not be construed in and of itself as an admission by any Reporting Person as to beneficial ownership of any Shares owned by another Reporting Person. BVF GP disclaims beneficial ownership of the Shares beneficially owned by BVF. BVF2 GP disclaims beneficial ownership of the Shares beneficially owned by BVF2. Partners OS disclaims beneficial ownership of the Shares beneficially owned by Trading Fund OS. BVF GPH disclaims beneficial ownership of the Shares beneficially owned by BVF and BVF2. Each of Partners, BVF Inc. and Mr. Lampert disclaims beneficial ownership of the Shares beneficially owned by BVF, BVF2 and Trading Fund OS and held in the Partners Managed Account, and the filing of this statement shall not be construed as an admission that any such person or entity is the beneficial owner of any such securities.
(b)
Percent of class:
The following percentages are based upon a denominator that is the sum of (i) 6,243,575 Shares outstanding, as of November 11, 2025, which is the total number of Shares outstanding as reported in the Issuer's Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission on November 12, 2025 and (ii) 1,017,464 Shares issued to the Reporting Persons and Partners Managed Account upon the exercise of certain Pre-Funded Warrants and Warrants previously held by the Reporting Persons and Partners Managed Account, as applicable, and (iii) 428,651 Shares issuable upon the exercise of certain Pre-Funded Warrants held by the Reporting Persons and the Partners Managed Account, as applicable.
As of the close of business on December 31, 2025, (i) BVF beneficially owned approximately 7.8% of the outstanding Shares, (ii) BVF2 beneficially owned approximately 2.3% of the outstanding Shares, (iii) Trading Fund OS beneficially owned 0% of the outstanding Shares, (iv) BVF GP may be deemed to beneficially own approximately 7.8% of the outstanding Shares, (v) BVF2 GP may be deemed to beneficially own approximately 2.3% of the outstanding Shares, (vi) Partners OS may be deemed to beneficially own 0% of the outstanding Shares, (vii) BVF GPH may be deemed to beneficially own approximately 9.9% of the outstanding Shares, and (viii) each of Partners, BVF Inc. and Mr. Lampert may be deemed to beneficially own approximately 9.99% of the outstanding Shares (less than 1% of the outstanding Shares are held in the Partners Managed Account).
(c)
Number of shares as to which the person has:
(i) Sole power to vote or to direct the vote:
See Cover Pages Items 5-9.
(ii) Shared power to vote or to direct the vote:
See Cover Pages Items 5-9.
(iii) Sole power to dispose or to direct the disposition of:
See Cover Pages Items 5-9.
(iv) Shared power to dispose or to direct the disposition of:
See Cover Pages Items 5-9.
Item 5.
Ownership of 5 Percent or Less of a Class.
Not Applicable
Item 6.
Ownership of more than 5 Percent on Behalf of Another Person.
If any other person is known to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, such securities, a statement to that effect should be included in response to this item and, if such interest relates to more than 5 percent of the class, such person should be identified. A listing of the shareholders of an investment company registered under the Investment Company Act of 1940 or the beneficiaries of employee benefit plan, pension fund or endowment fund is not required.
BVF GP, BVF GPH, Partners, BVF Inc. and Mr. Lampert share voting and dispositive power over the Shares beneficially owned by BVF. BVF GPH, Partners, BVF Inc. and Mr. Lampert share voting and dispositive power over the Shares beneficially owned by BVF2. Partners, BVF Inc. and Mr. Lampert share voting and dispositive power over the Shares beneficially owned by Trading Fund OS and held in the Partners Managed Account.
Item 7.
Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
Not Applicable
Item 8.
Identification and Classification of Members of the Group.
If a group has filed this schedule pursuant to §240.13d-1(b)(1)(ii)(J), so indicate under Item 3(j) and attach an exhibit stating the identity and Item 3 classification of each member of the group. If a group has filed this schedule pursuant to §240.13d-1(c) or §240.13d-1(d), attach an exhibit stating the identity of each member of the group.
See Exhibit 99.1 to the Schedule 13G filed with the Securities and Exchange Commission on August 19, 2024.
Item 9.
Notice of Dissolution of Group.
Not Applicable
Item 10.
Certifications:
By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under ?? 240.14a-11.
SIGNATURE
After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.
What stake does BVF report in Tenax Therapeutics (TENX)?
BVF-related entities report beneficial ownership of about 9.99% of Tenax common stock, or 768,200 shares
How many Tenax shares are tied to BVF’s pre-funded warrants?
BVF and a managed account hold pre-funded warrants exercisable for 10,099,974 Tenax shares. Because of a 9.99% ownership blocker, only 428,651 underlying shares are currently counted as beneficially owned; the remainder are excluded until the blocker allows further exercise.
What additional Tenax warrants do the BVF entities hold?
The reporting group holds 5,209,174 additional warrants for Tenax shares or pre-funded warrants. These are immediately exercisable in principle but are effectively blocked at December 31, 2025 by a 9.99% beneficial ownership cap that currently prevents any warrant exercise.
Which BVF entities may be deemed to share control over Tenax shares?
Entities such as BVF GP Holdings LLC, BVF Partners L.P., BVF Inc. and Mark N. Lampert may be deemed to share voting and dispositive power over Tenax shares held by BVF funds and a managed account, although several entities formally disclaim beneficial ownership of affiliates’ holdings.
Does BVF’s Tenax position aim to change control of the company?
The reporting group certifies that Tenax securities were not acquired or held with the purpose or effect of changing or influencing control. They state the holdings are not part of any transaction intended to influence control, aside from potential nomination activities referenced under SEC proxy rules.
What percentage of Tenax does each BVF fund individually own?
As of December 31, 2025, Biotechnology Value Fund, L.P. beneficially owns about 7.8% of Tenax common stock, and Biotechnology Value Fund II, L.P. beneficially owns about 2.3%. The trading fund reports 0% beneficial ownership, with its warrant and pre-funded warrant exposure excluded by blockers.
