Interim report as at September 30, 2025

BB Biotech

Belevue Heathcae Investments

Interim Report as at 30.09.2025

Table of contents

Business Report 3-13

Performance/Multi-year comparison 3

Shareholder letter 7

Portfolio at a glance 13

Financial Report 14-25

Consolidated interim financial statements 14

Selected explanatory notes to the consolidated interim financial statements 18

Report of the statutory auditors 25

About us 26-36

Company profile 26

Investment strategy 27

Investment process 29

Board of Directors 31

Investment Manager 31

Shareholder information 32

Facts & figures 33

Corporate calendar 34

Contact 35

Performance/Multi-year comparison

Indexed performance since launch

BB Biotech AG (SIX)-CHF

0

NAV CHF indexed Share Price CHF indexed Nasdaq Biotech Index (NBI) TR indexed

Cumulated performance

30.09.2025

Annualized performance

30.09.2025

109.11.1993

109.11.1993

BB BIOTECH AG (XETRA)-EUR

0

NAV EUR indexed Share Price EUR indexed Nasdaq Biotech Index (NBI) TR indexed

Cumulated performance

30.09.2025

Annualized performance

30.09.2025

110.12.1997

110.12.1997

Multi-year comparison

1All figures in CHF %, total return-methodology

2Based on market capitalization

Shareholder letter

Dear Shareholders

After a volatile first half, BB Biotech delivered a strong third quarter. Our share price and NAV outpaced the Nasdaq Biotechnology Index (NBI), while a sequence of clinical, regulatory, and M&A milestones reinforced the momentum building across the biotechnology sector. Macro conditions have turned incrementally more constructive: in September, the US Federal Reserve enacted its first rate cut of 2025, lowering the target range to 4.00-4.25% and signalling a gradual normalization of financing conditions for capital-intensive industries.

Markets are now beginning to price a path toward additional easing as inflation cools, offering renewed support to innovative growth sectors such as biotechnology.

Beyond cyclical relief, signs of structural improvement are emerging across the industry's long-term economics. Early signs of recovery are visible as global pharmaceutical pricing begins to adjust to new market realities, formed by tariffs and price referencing. At the same time, the sector is approaching the largest patent cliff in its history, prompting renewed strategic M&A and partnership activity. These dynamics are compressing timelines between scientific discovery and value recognition, benefiting differentiated innovators.

Despite this improving backdrop, valuations remain attractive. As financing costs decline and balance sheets remain solid, the setting for a multi-year re-rating is emerging.

The long-term fundamentals of biotechnology remain robust. A growing and aging population continues to drive demand for therapies addressing chronic and age-related diseases. Innovation is accelerating, with progress in RNA medicines, next-generation biologics, targeted small molecules, and other precision approaches. These advances, combined with data-driven research and AI-assisted design, are reshaping the global biomedical development and collaboration.

Public research funding is being reorganized, and governments are reshaping how medicines are priced and reimbursed through tariffs, reference systems, and new industry agreements. Despite these adjustments, incentives for developing truly innovative therapies remain strong. The FDA is also refining its processes, becoming faster in some areas and more selective in others, while continuing to set the global regulatory standard. Recent initiatives such as the new National Priority Voucher program underline the agency's commitment to accelerating reviews for therapies addressing high unmet medical needs.

During the recent government shutdown, the agency maintained review operations but paused new submissions, allowing ongoing evaluations to proceed largely as planned.

Together, these developments point to a sector whose fundamentals are strengthening even as its valuation base resets. The signs of renewed momentum are clear: capital is returning, strategic acquirers are active, and science continues to accelerate. For BB Biotech, this environment reinforces our conviction that a disciplined, innovation-driven, and patient investment approach is the best way to capture the next phase of value creation.

Importantly, our own sustainability journey also reached a new milestone: as of September 22, BB Biotech was included in the SPI ESG Index on the SIX Swiss Exchange, recognizing our long-standing commitment to responsible investing and transparent corporate governance.

Strong Q3 2025 performance and encouraging momentum

BB Biotech delivered a strong third quarter, marked by a convincing absolute and relative performance. Both the share price and NAV rose sharply, clearly outpacing the Nasdaq Biotechnology Index (NBI). The combination of lower interest rates, broad sector recovery,

and solid operational execution across key holdings translated into a significant uplift in value.

Notable NAV performance. The Net Asset Value (NAV) advanced by 24.0% in CHF and EUR and 23.5% in USD, outperforming the NBI (+15.7%) by a wide margin. The quarter closed with a net profit of CHF 448 mn, one of the strongest results in recent years and a clear reversal from the CHF 157 mn loss in Q3 2024.

Strong share price recovery. BB Biotech's share price increased by 20.0% in CHF, 20.1%

in EUR and 19.5% in USD, again outpacing the NBI across all currencies.

Stable valuation and rising engagement. While the discount to NAV remained broadly unchanged, higher trading activity and increased investor participation signaled a clear rebound in sentiment toward the biotech sector and BB Biotech's focused portfolio.

Together, these results confirm that BB Biotech has regained clear momentum. The portfolio benefited from strong operational execution among core holdings, selective exposure to M&A activity, and the supportive macroeconomic environment following the September rate cut. With conviction positions intact and valuations still attractive, BB Biotech enters the fourth quarter from a position of strength.

With conviction positions intact and valuations still attractive, BB Biotech enters the fourth quarter from a position of strength.

Portfolio highlights: innovation driving progress in Q3

Q3 2025 brought a number of important milestones across our portfolio, underscoring our conviction that scientific innovation is the most enduring driver of long-term value creation. Our holdings made meaningful progress on regulatory, commercial, and clinical fronts. Some highlights include:

Regulatory and commercial execution

Ionis Pharmaceuticals: September was a landmark month for Ionis. The company announced positive Phase III results for Olezarsen in severe hypertriglyceridemia, confirming significant triglyceride reduction and a favorable safety profile. Later in the month, Ionis reported encouraging Phase I/II results for Zilganersen in Alexander disease, showing the first clinical evidence of disease stabilization. Together with the August FDA approval of Donidalorsen (Dawnzera) for hereditary angioedema, these achievements further cement Ionis's leadership in RNA-based medicines.

Alnylam Pharmaceuticals: Strong launch momentum for Amvuttra in transthyretin amyloidosis and positive interim data from next-generation candidates supported broad franchise expansion.

Argenx: Continued uptake of Vyvgart across both intravenous and subcutaneous formulations drove solid commercial growth, while regulatory submissions for additional indications advanced globally.

Agios Pharmaceuticals: Progress toward the expected approval of Mitapivat in thalassemia and further clinical expansion into sickle cell disease strengthened its rare-disease positioning.

Clinical breakthroughs and translational momentum

Revolution Medicines: Early data for Daraxonrasib (KRAS-Multi) and Zoldonrasib (KRAS-G12D) confirmed high response rates and strong investor interest following Breakthrough Therapy designation.

Scholar Rock: Preparation of a resubmission for Apitegromab following the FDA's manufacturing-related Complete Response Letter kept this potential first-in-class SMA therapy on track for 2026 launch.

Vertex Pharmaceuticals: Continued post-launch strength of Journavx (VX-548) and encouraging progress in its autoimmune kidney disease programs underlined Vertex's ambition to build franchises beyond cystic fibrosis.

Rivus Pharmaceuticals: Positive Phase II data in MASH confirmed the differentiation of its controlled mitochondrial uncoupling approach.

Relay Therapeutics: Readiness for pivotal Phase III initiation of RLY-2608 (PI3Kα) in HR⁺/ HER2⁻ breast cancer supports its evolution into a late-stage precision-oncology company.

Collectively, these achievements demonstrate how BB Biotech's conviction in scientifically differentiated, well-capitalized mid-cap innovators continues to translate into both portfolio resilience and performance.

Sharpening the portfolio: active rotation and strategic focus

Disciplined capital allocation and portfolio rotation remain central to our investment strategy. We continuously refine the portfolio to concentrate on companies with the most differentiated science, clear value-creation pathways, and sustainable financial strength.

During the third quarter, we adjusted the portfolio from 23 to 21 holdings, keeping the investment level broadly stable at 96.6%.

Exits: Moderna, Black Diamond Therapeutics and Blueprint Medicines. We fully exited our positions in Moderna, Black Diamond Therapeutics and Blueprint Medicines. Moderna's long-term vaccine outlook remains uncertain amid changing public health priorities and lower demand for COVID-related products under the current US administration. In addition, increased regulatory scrutiny and societal skepticism toward vaccines continue to weigh on sentiment, reducing the visibility of near-term catalysts. We also sold our stake in Black Diamond Therapeutics following a reassessment of its clinical competitiveness and strategic optionality. Despite progress in early oncology programs, the company faced intensifying competition and limited differentiation versus peers. These two exits freed capital for higher-conviction opportunities within the portfolio. Our position in Blueprint Medicines was closed following the completion of Sanofi's acquisition in July.

New investment: Avidity Biosciences. In Q3, we initiated a position in Avidity Biosciences, a leader in antibody-oligonucleotide conjugates (AOC). The company's proprietary AOC platform combines targeted delivery with RNA-based precision, addressing key challenges in muscle and rare genetic diseases. Recent clinical progress in myotonic dystrophy (DM1) and facioscapulohumeral muscular dystrophy (FSHD) demonstrates proof of concept and underpins meaningful upside potential. Avidity's strong balance sheet and diversified partnership base further support its long-term growth profile.

Selective reinvestment. Positions increased notably in Revolution Medicines, Akero Therapeutics, Scholar Rock and other mid-cap innovators, reflecting both strong share-

price performance and targeted capital redeployment. The addition of Avidity Biosciences further enhanced exposure to next-generation RNA therapeutics.

These portfolio adjustments reflect our commitment to maintaining a focused group of highquality innovators while reallocating capital toward the most compelling scientific and financial opportunities. By staying selective and responsive, BB Biotech remains well positioned to capture emerging value across the sector. The announced acquisition of Akero Therapeutics by Novo Nordisk in early October, shortly after the quarter's close, illustrates how strategic buyers continue to reward differentiated science. Generally the third quarter was marked by a series of major acquisitions in the biopharmaceutical industry - including transactions by Pfizer (Metsera), Roche (89bio), Genmab (Merus) and Merck (Verona Pharma), each involving multi-billion-dollar valuations. These developments highlight the continued strong interest of large pharmaceutical companies in innovative, scientifically differentiated platforms and leading biotech assets, as well as their willingness to pay substantial premiums for quality innovation.

The portfolio currently sits at the lower end of our target range in terms of the number of holdings. This creates room to expand the tail with new, high-potential positions while maintaining our core convictions. With a solid cash position, an enlarged US research team providing deeper market coverage, and a broad set of attractively valued opportunities across the biotech universe, BB Biotech is well equipped to deploy capital selectively and to strengthen both the depth and diversity of its portfolio in the coming quarters.

Portfolio breakdown of BB Biotech as of September 30, 2025

Advancing our strategy: executing with discipline, evolving with insight, deepening shareholder alignment

The third quarter reaffirmed that sustainable long-term value in biotechnology comes from a combination of conviction, adaptability, and continuous improvement. Our strategic framework continues to rest on three key principles:

High-conviction concentration: We maintain a focused portfolio of 21 companies, currently at the lower end of our 20-35 position range. This concentration allows us to back the most compelling innovation platforms with meaningful capital while keeping flexibility to expand the tail as new opportunities emerge. Our permanent capital structure enables us to act on long-term conviction - investing through volatility and capturing

value as science and market sentiment realign. Q3's strong performance, driven by Ionis Pharmaceuticals, Alnylam Pharmaceuticals, Argenx, and Agios Pharmaceuticals, highlights the benefit of holding mid-cap innovators at clear clinical and commercial inflection points.

Dynamic capital allocation: Our S-curve investment model continues to guide capital toward companies moving from research to commercialization, where valuation upside is promising. During the quarter, we exited Moderna and Black Diamond Therapeutics and initiated a new position in Avidity Biosciences, strengthening our exposure to next-generation RNA therapeutics. This approach keeps the portfolio agile and focused on the most attractive opportunities across therapeutic areas.

Process evolution and agentic AI integration: We continue to refine our investment process through a more systematic framework for managing risk, exposure, and time horizons. A structured, gate-based approach helps maintain long-term focus while enabling tactical agility within defined conviction ranges. By progressively digitalizing our workflow, we are enhancing transparency, measurability, and analytical depth across all stages of the investment process. The ongoing integration of AI-assisted tools supports earlier identification of opportunity, clearer assessment of risk-adjusted returns, and improved decision consistency - strengthening both human and data-driven insight over time.

BB Biotechʼs S-curve model

Outlook: turning innovation into enduring value

As we look ahead to the remainder of 2025 and into 2026, we maintain a constructive, however realistic view of the environment for biotech investing. The macroeconomic backdrop continues to improve. The Federal Reserve's first rate cut in September lowered the policy range to 4.00-4.25%, reinforcing expectations for further easing in 2026 as inflation moderates. Lower funding costs are beginning to support capital-intensive sectors such as biotechnology.

Policy visibility has improved as recent developments in US healthcare legislation and the Pfizer agreement have brought greater clarity to drug pricing and trade dynamics. The debate around pharmaceutical tariffs and Most-Favored-Nation frameworks has stabilized, and the rollout of Medicare negotiations under the Inflation Reduction Act is progressing in a more predictable way. At the same time, the FDA's review activity remains consistent, providing a supportive regulatory environment for innovation.

Moreover, scientific innovation is accelerating. BB Biotech's portfolio companies are advancing multiple programs with the potential to deliver value-defining catalysts over the coming quarters. Recent approvals such as Donidalorsen (Ionis) and strong late-stage data for Olezarsen highlight the strength of RNA-based medicine.

Expected regulatory approvals and launches:

Mitapivat (Agios Pharmaceuticals) - α/β-thalassemia

Troriluzole (Biohaven) - spinocerebellar ataxia

Apitegromab (Scholar Rock) - spinal muscular atrophy (resubmission expected for 2026)

Pivotal data and late-stage catalysts expected for Q4 2025:

Mitapivat (Agios Pharmaceuticals) - Phase III results in sickle cell disease

WVE-006 (Wave Life Sciences) - Phase I/II data RNA editing in alpha-1-antitrypsin-

deficiency (AATD)

NBI-'770 (Neurocrine Biosciences) - Phase II results in major depressive disorder

EDG-7500 (Edgewise Therapeutics) - CIRRUS-HCM Part D Phase II data in hypertrophic

cardiomyopathy (HCM)

INCB160058 (Incyte) - Phase I/II data for JAK2 V617F in myeloproliferative neoplasms

RLY-2608 (Relay Therapeutics) - Phase I/II PI3Kα triplet data in first-line breast cancer

Looking ahead, our portfolio is positioned to benefit from a series of expected milestones, including pivotal and proof-of-concept readouts across key holdings in metabolic, cardiovascular, and neurological diseases. These clinical and commercial inflection points reflect the continued shift of innovation toward specialized, well-capitalized mid-cap companies - precisely the area where BB Biotech is most active.

Beyond portfolio activity, we continue to strengthen our analytical and technological foundation. The gradual rollout of AI-assisted research tools and the expansion of our US research capabilities are enhancing our ability to assess opportunity, manage risk, and communicate insights transparently with shareholders.

Biotech valuations remain near historic lows, even as fundamentals improve and innovation gathers pace. This combination of attractive entry points, accelerating science, and improving capital conditions represents one of the most compelling circumstances for longterm investors in recent years.

We enter the final quarter of 2025 with confidence. The convergence of breakthrough science, intelligent infrastructure, and a long-term investment horizon gives BB Biotech a clear edge in identifying and capturing enduring value for shareholders.

Thank you for your continued trust and partnership. The Board of Directors of BB Biotech AG

Dr. Thomas von Planta

Chairman Laura Hamill Member

Camilla Soenderby

Member

Dr. Clive Meanwell

Vice-Chairman Dr. Pearl Huang Member

Prof. Dr. Mads Krogsgaard Thomsen

Member

Portfolio at a glance

Securities as at September 30, 2025

Company Number Change Local Share Market In % of In % of In % of of since currency price value securities shareholders' company securities 31.12.2024 in CHF mn equity

1Unlisted company

Exchange rate as at 30.09.2025: USD/CHF: 0.7964

Consolidated balance sheet

The notes are an integral part of the condensed consolidated interim financial statements.

The condensed consolidated interim financial statements were approved by the Board of Directors of BB Biotech AG on October 21, 2025.

Consolidated statement of comprehensive income

The notes are an integral part of the condensed consolidated interim financial statements.

Consolidated statement of changes in equity

The notes are an integral part of the condensed consolidated interim financial statements.

Consolidated statement of cash flows

The notes are an integral part of the condensed consolidated interim financial statements.

Notes to the consolidated financial statements

1. The Company and its principal activity

   BB Biotech AG (the Company) is listed on the SIX Swiss Exchange as well as in the «Prime Standard Segment» of the German Exchange and has its registered office in Schaffhausen, Schwertstrasse 6. Its principal activity is to invest in companies active in the biotechnology industry for the purpose of capital appreciation. The investments are held through its wholly owned subsidiaries.

   Company		Capital in CHF 1 000		Capital and voting interest in %
   Biotech Focus N.V., Curaçao		11		100
   Biotech Growth N.V., Curaçao		11		100
   Biotech Invest N.V., Curaçao		11		100
   Biotech Target N.V., Curaçao		11		100

2. Accounting policies

   The condensed consolidated interim financial statements of the Company and its subsidiary companies (the Group) have been prepared in accordance with International Accounting Standards (IAS) 34 «Interim Financial Reporting», as well as the provisions of the rules of the SIX Swiss Exchange for Investment Companies and should be read in conjunction with the consolidated annual financial statements for the year ended December 31, 2024. The preparation of the condensed consolidated interim financial statements requires management to make assumptions and estimates that have an impact on the balance sheet values and items of the statement of comprehensive income in the current financial period. In certain circumstances, the actual values may diverge from these estimates.

   The condensed consolidated interim financial statements have been prepared in accordance with the accounting policies set out in the consolidated annual financial statements.

   The following amended standard, valid since January 1, 2025, has been applied in these condensed consolidated interim financial statements:

   IAS 21 (amended, effective January 1, 2025) - Lack of Exchangeability
   
   

   The following new and amended standards were approved, but will only be applicable for the Group prospectively and were not early adopted in these condensed consolidated interim financial statements:

   IFRS 9/IFRS 7 (amended, effective January 1, 2026) - Classification and Measurement of
   
   

   Financial Instruments

   IFRS 18 (effective January 1, 2027) - Presentation and Disclosure in Financial Statements
   
   
   IFRS 19 (effective January 1, 2027) - Subsidiaries without Public Accountability:
   
   

   Disclosures

   The Group assessed the potential impact of the above-mentioned new and amended standards. Based on the analysis, the Group concludes that these new and amended standards have no material impact on the Group's accounting policies and overall results and financial position.

   The following exchange rates have been used for the preparation of these condensed consolidated interim financial statements:

   Currency		30.09.2025		31.12.2024
   USD		0.79640		0.90740
   XCG 1)		0.44742		0.50978
   EUR		0.93450		0.94008
   GBP		1.07090		1.13560

   1since April 1, 2025, Caribbean Guilder, before ANG (Antillean Guilder)

3. Financial assets

   Fair Values

   The following table presents the Group's assets that are measured at fair value (in CHF 1 000):

   30.09.2025		Level 1		Level 2		Level 3		Total
   Assets Securities - Shares		2 185 004		-		43 422		2 228 426
   - Derivative instruments		-		104		-		104
   Total assets		2 185 004		104		43 422		2 228 530
   31.12.2024
   Assets Securities - Shares		2 369 436		-		37 444		2 406 881
   - Derivative instruments		-		-		-		-
   Total assets		2 369 436		-		37 444		2 406 881

   The table below summarizes the transactions in level 3 instruments (in CHF 1 000):

   		01.01.-30.09.2025		01.01.-30.09.2024
   Opening balance		37 444		14 725
   Purchases		12 079		15 139
   Unrealized gains/(losses) included in gains/losses from securities		(6 101)		5 030
   Closing balance		43 422		34 894
   Gains/(losses) on level 3 instruments included in gains/losses from securities		(6 101)		5 030

   There were no transfers between level 1, 2 and 3 during the reporting period.

   The fair value of level 3 instruments at initial recognition represents the transaction price (purchase of preferred stocks of Rivus Pharmaceuticals in August 2022 for TCHF 16 875, August 2024 for TCHF 15 139 and January 2025 for TCHF 12 079), which was paid in financing rounds together with other investors. For the valuation as at September 30, 2025, it is deemed to be appropriate to use the latest transaction price in USD, as it is a reasonable approximation of fair value at the valuation date, based on the information available and in the absence of developments that would reasonably be expected to materially affect fair value.

   In August 2022, 8 733 538 Radius Health - Contingent Value Rights were allocated from a

   corporate action. In February 2025 BB Biotech received USD 1 per Right.

   For assets and liabilities carried at amortised cost, their carrying values are a reasonable approximation of fair value.

   Securities

   The changes in value of securities at fair value through profit or loss by investment category are as follows (in CHF 1 000):

   		Listed shares		Unlisted shares		Derivative instruments		Total
   Opening balance as at 01.01.2024 at fair values		2 619 989		14 725		-		2 634 714
   Purchases		206 303		15 139		316		221 758
   Sales		(561 097)		-		(42)		(561 139)
   Gains/(losses) from securities		104 241		7 581		(274)		111 548
   Realized gains		107 900		-		-		107 900
   Realized losses		(46 182)		-		(274)		(46 456)
   Unrealized gains		480 172		7 581		-		487 753
   Unrealized losses		(437 649)		-		-		(437 649)
   Closing balance as at 31.12.2024 at fair values		2 369 436		37 444		-		2 406 881
   Opening balance as at 01.01.2025 at fair values		2 369 436		37 444		-		2 406 881
   Purchases		399 037		12 079		-		411 116
   Sales		(714 941)		-		(7 900)		(722 841)
   Gains/(losses) from securities		131 471		(6 101)		8 004		133 375
   Realized gains		162 350		-		7 900		170 250
   Realized losses		(76 110)		-		-		(76 110)
   Unrealized gains		240 414		-		104		240 518
   Unrealized losses		(195 183)		(6 101)		-		(201 284)
   Closing balance as at 30.09.2025 at fair values		2 185 004		43 422		104		2 228 530

   Securities comprise the following:

   Company		Number 31.12.2024		Change		Number 30.09.2025			Market price in original currency 30.09.2025		Valuation CHF mn 30.09.2025		Valuation CHF mn 31.12.2024
   Ionis Pharmaceuticals		7 850 000		(1 625 162)		6 224 838		USD	65.42		324.3		249.0
   Argenx SE		591 000		(55 678)		535 322		USD	737.56		314.4		329.8
   Revolution Medicines		4 374 300		1 192 700		5 567 000		USD	46.70		207.0		173.6
   Neurocrine Biosciences		1 820 000		(60 000)		1 760 000		USD	140.38		196.8		225.4
   Alnylam Pharmaceuticals		760 000		(321 321)		438 679		USD	456.00		159.3		162.3
   Vertex Pharmaceuticals		475 000		(17 200)		457 800		USD	391.64		142.8		173.6
   Agios Pharmaceuticals		3 515 150		199 586		3 714 736		USD	40.14		118.8		104.8
   Incyte		2 150 000		(714 145)		1 435 855		USD	84.81		97.0		134.7
   Scholar Rock Holding		2 486 707		750 670		3 237 377		USD	37.24		96.0		97.5
   Akero Therapeutics		-		2 382 755		2 382 755		USD	47.48		90.1		-
   Immunocore		1 205 464		1 591 339		2 796 803		USD	36.33		80.9		32.3
   Avidity Biosciences		-		2 152 862		2 152 862		USD	43.57		74.7		-
   Celldex Therapeutics		3 071 615		486 054		3 557 669		USD	25.87		73.3		70.4
   Beam Therapeutics		1 518 121		1 371 167		2 889 288		USD	24.27		55.8		34.2
   Edgewise Therapeutics		1 428 929		1 347 068		2 775 997		USD	16.22		35.9		34.6
   Relay Therapeutics		7 375 000		968 318		8 343 318		USD	5.22		34.7		27.6
   Biohaven		2 040 853		762 000		2 802 853		USD	15.01		33.5		69.2
   Wave Life Sciences		4 094 458		-		4 094 458		USD	7.32		23.9		46.0
   Macrogenics		9 929 963		(9 971)		9 919 992		USD	1.68		13.3		29.3
   Annexon		5 157 290		-		5 157 290		USD	3.05		12.5		24.0
   Intra-Cellular Therapies		2 425 000		(2 425 000)		-		USD	n.a.		-		183.8
   Moderna		1 600 000		(1 600 000)		-		USD	25.83		-		60.4
   Arvinas		2 380 000		(2 380 000)		-		USD	8.52		-		41.4
   Sage Therapeutics		4 460 693		(4 460 693)		-		USD	n.a.		-		22.0
   Esperion Therapeutics		9 944 064		(9 944 064)		-		USD	2.65		-		19.9
   Black Diamond Therapeutics		8 517 839		(8 517 839)		-		USD	3.79		-		16.5
   Fate Therapeutics		4 839 779		(4 839 779)		-		USD	1.26		-		7.2
   Blueprint Medicines		-		-		-		USD	n.a.		-		-
   Listed shares											2 185.0		2 369.5
   Rivus Pharmaceuticals								USD			43.4		37.4
   Unlisted shares											43.4		37.4
   Total shares											2 228.4		2 406.9
   Blueprint Medicines - Contingent Value Right		-		284 900		284 900		USD	0.46		0.1		-
   Molecular Templates - Warrants, 2.4.29		769 334		(769 334)		-		USD	n.a.		-		-
   Radius Health - Contingent Value Right		8 733 538		(8 733 538)		-		USD	n.a.		-		-
   Total derivative instruments											0.1		-
   Total securities											2 228.5		2 406.9

4. Short-term borrowings from banks

   At September 30, 2025, there is no short-term loan outstanding (December 31, 2024:

   CHF 117.5 mn at 0.90% p.a.).

5. Shareholders' equity

The share capital of the Company consists of 55.4 mn fully paid registered shares

(December 31, 2024: 55.4 mn) with a par value of CHF 0.20 each (December 31, 2024:

CHF 0.20).

Treasury shares

The Company can buy and sell treasury shares in accordance with the Company's articles of association and Swiss company law and in compliance with the listing rules of the SIX Swiss Exchange. During the period from January 1, 2025, to September 30, 2025, the Company has bought 166 750 treasury shares and has sold 554 000 treasury shares (01.01.-30.09.2024: Purchase of 20 000 treasury shares, no sales). As at September 30, 2025, the Company holds 250 750 treasury shares (December 31, 2024: 638 000 shares). The treasury shares as at September 30, 2025, were treated as a deduction from the consolidated shareholders' equity using cost values of TCHF 8 169 (December 31, 2024: TCHF 39 640).

Share buyback 2ndline (bought for cancellation)

The Board of Directors has approved the repurchase of a maximum of 5 540 000 own registered shares with a nominal value of CHF 0.20 each. Until the end of the program at April 11, 2025, 250 750 registered shares were repurchased via a second trading line for the purpose of capital reduction (December 31, 2024: 84 000 shares).

The remuneration model of BB Biotech AG is determined by the Board of Directors.

Since 2014 the remuneration paid to the investment manager is based upon a 1.1% p.a. all-in fee on the average market capitalization without any additional fixed or performance-based elements of compensation. The compensation of the Board of Directors consists since 2014 of a fixed compensation.

1. Segment reporting

   The sole operating segment of the Group reflects the internal management structure and is evaluated on an overall basis. Revenue is derived by investing in a portfolio of companies active in the biotechnology industry for the purpose of capital appreciation. The following results correspond to the sole operating segment of investing in companies active in the biotechnology industry.

   The geographical analysis of the profit/(loss) before tax is as follows - all income from financial assets are attributed to a country based on the domiciliation of the issuer of the instrument.

   Profit/(loss) before tax in CHF 1 000		01.01.-30.09.2025		01.01.-30.09.2024
   USA		182 777		(35 702)
   Netherlands		14 470		97 442
   Great Britain		5 710		(32 457)
   Canada		-		(3 380)
   Switzerland		(12 102)		(9 726)
   Curaçao		(16 054)		(24 613)
   Singapore		(22 089)		11 727
   British Virgin Islands		(46 219)		13 009
   		106 493		16 300

2. Earnings per share

   		01.01.-30.09.2025		01.01.-30.09.2024
   Total comprehensive profit/(loss) for the period (in CHF 1 000)		106 448		16 243
   Weighted average number of shares in issue		54 753 976		54 842 000
   Earnings per share in CHF		1.94		0.30
   Income used to determine diluted earnings per share (in CHF 1 000)		106 448		16 243
   Weighted average number of shares in issue following the dilution		54 753 976		54 842 000
   Diluted earnings per share in CHF		1.94		0.30

3. Assets pledged

   At September 30, 2025, securities in the amount of CHF 2 228.5 mn (December 31, 2024: CHF 2 406.9 mn) are collateral for a credit line of CHF 700 mn (December 31, 2024:

   CHF 700 mn). At September 30, 2025, there is no short-term loan outstanding

   (December 31, 2024: CHF 117.5 mn).

4. Transactions with the Investment Manager and related party transactions

   Detailed information regarding the remuneration model for the Board of Directors and the investment manager are mentioned under note «6. Administrative Expenses».

5. Commitments, contingencies and other off-balance sheet transactions

   The Group had no commitments or other off-balance sheet transactions open at

   September 30, 2025 and December 31, 2024.

   The operations of the Group are affected by legislative, fiscal and regulatory developments for which provisions are made where deemed necessary. The Board of Directors concludes that as at September 30, 2025, no proceedings existed which could have any material effect on the financial position of the Group (December 31, 2024: none).

6. Subsequent events

There have been no events subsequent to September 30, 2025, which would affect the condensed consolidated interim financial statements.

Report on the review of condensed consolidated interim financial statements

Introduction

We have reviewed the accompanying condensed consolidated balance sheet of BB Biotech AG as of September 30, 2025 and the related condensed consolidated statements of income, changes in equity and cash flows for the nine-month period then ended, and a summary of significant accounting policies and other explanatory notes. The Board of Directors is responsible for the preparation and presentation of this interim financial information in accordance with International Accounting Standard 34 «Interim Financial Reporting» and article 14 of the Directive on Financial Reporting of the SIX Swiss Exchange. Our responsibility is to express a conclusion on this interim financial information based on our review.

Scope of Review

We conducted our review in accordance with the Swiss Auditing Standard 910 (SAS 910)

«Engagements to Review Financial Statements» and the International Standard on Review Engagements (ISRE) 2410 «Review of interim financial information performed by the independent auditor of the entity». A review of interim financial information consists of making inquiries, primarily of persons responsible for financial and accounting matters, and applying analytical and other review procedures. A review is substantially less in scope than an audit conducted in accordance with International Standards on Auditing and consequently does not enable us to obtain assurance that we would become aware of all significant matters that might be identified in an audit. Accordingly, we do not express an audit opinion.

Conclusion

Based on our review, nothing has come to our attention that causes us to believe that the accompanying condensed consolidated interim financial information for the nine months ended September 30, 2025 are not prepared, in all material respects, in accordance with International Accounting Standard 34 Interim Financial Reporting and article 14 of the Directive on Financial Reporting of the SIX Swiss Exchange.

Deloitte AG

Chris Krämer Licensed Audit Expert Auditor in Charge Mathieu Valette

Licensed Audit Expert

Zurich, 22 October 2025

Deloitte AG, Pfingstweidstrasse 11, CH-8005 Zurich

Phone: +41 (0)58 279 60 00, Fax: +41 (0)58 279 66 00, https://www.deloitte.ch

Company profile

Commitment to Biotech Investments

The access to fast growing biotechnology companies

BB Biotech invests in companies in the fast growing market of biotechnology and is one of the world's largest investors in this sector with more than 30 years of experience. The shares of BB Biotech are listed on the SIX Swiss Exchange and the Frankfurt Stock Exchange. Its investments are focused on listed companies that are developing and commercializing novel drugs that offer sound value for the healthcare system.

The competent Board of Directors with its long-standing experience set the investment strategy and guidelines. Investment decisions are taken by the experienced investment management team of Bellevue Asset Management AG based on their extensive investment research.

Mega trends such as increasing life expectancy and a Westernized diet and lifestyle are powerful growth drivers. These mega trends have led to a tremendous increase in healthcare costs, which, in turn, only amplifies the need for more efficient and effective drugs.

Investment strategy

BB Biotech invests in fast-growing biotechnology companies that are developing and marketing innovative drugs. It focuses on biotech companies whose products address areas of significant unmet medical needs and thus have above-average sales and profit-growth potential.

Besides profitable large cap companies, BB Biotech is building up its investments in promising small and mid cap companies.

The team of investment experts is concentrating not only on established target areas such as oncology, orphan diseases and neurological indications, but also on the technologies of tomorrow that could lead to novel treatment methods with attractive therapeutic profiles and substantial economic rewards. These future technologies include RNA platforms and cell and gene therapies. An overall weighted average cost of capital (WACC) of at least 15% is applied to the discounted cash flow models of our portfolio, aligned with our mid-to long term investment objectives.

The asset classes available to BB Biotech are direct investments in the shares of listed companies, equity interests in unlisted companies, corporate bonds, and options on a range of underlying assets. BB Biotech invests almost exclusively in stocks for liquidity and risk/ return reasons. At least 90% of its shareholdings must be in listed companies, while always holding more than 50% of its assets in equity investments. Corporate bonds are an alternative primarily when stock market trends are negative. Options on the stocks of portfolio companies can be bought and sold at opportune times and as a means of hedging currency exposure.

We are focussing on the technologies of tomorrow.

Multi-stage due diligence process based on bottom-up fundamental analysis

Exhaustive, multi-stage due diligence precedes the selection of individual investments. We must have a thorough understanding of every company we invest in. Before an investment is made, the team analyzes a company's financial statements in detail and assesses its competitive environment, R&D pipeline, and patent portfolio as well as its customers' perceptions of its products and services.

Close contact with company executives is of high importance to us in this due diligence process, but also afterwards, as we believe that it takes strong leaders to achieve strong results.

BB Biotech relies on the long-standing experience of its distinguished Board of Directors and on the fundamental analysis of the experienced Investment Management Team of Bellevue Asset Management AG when making its investment decisions. It can also turn to an extensive international network of physicians and specialists in individual sub-segments of the biotech industry for further support and advice.

The Investment Management Team creates detailed financial models for all portfolio holdings and they must provide compelling arguments that these holdings have the potential to double in value over a four-year time frame. The team is guided by its convictions, not by benchmark considerations. Upside potential is driven in most cases by the power of innovation, the launch of new products for serious or significant illnesses, and successful company management. Each investment case is constantly monitored and evaluated within the scope of our stringent and disciplined risk management process and corrective action will be taken if and when necessary.

We follow our own conviction, not a benchmark.

High conviction portfolio consisting of a maximum of 35 positions

BB Biotech's investment portfolio will usually consist of between 20 to 35 biotechnology companies. There are estblished large cap companies as well as small and mid cap companies in the portfolio. Smaller positions will be taken in innovative biotech companies with promising R&D pipelines. From a regional perspective, the US biotech sector has displayed a high level of innovation and so this regional bias is also reflected in BB Biotech's portfolio. The predominance of the US biotech industry can be traced to the country's stellar research clusters, industry-friendly regulatory frameworks and myriad financing options, among other factors.

New investments in small and mid cap companies will have a weighting of between 0.5% and a maximum of 4% to ensure that both upside potential and R&D risks are adequately addressed. Because it is a holding company, BB Biotech has the flexibility to increase portfolio weightings considerably over time as a position increases in value. Smaller positions may become a top holding as their business develops and milestones such as positive Phase III outcomes, drug approvals, the successful marketing of products, and a sustainable flow of profits are achieved. All positions and their valuations are continually monitored, taking into account their growth potential and other aspects, and will be reduced if and when appropriate.

Investment process

During the investment selection process, BB Biotech relies on the well established experience of its Board of Directors and the fundamental analyses by the experienced management team of Bellevue Asset Management AG, with access to a network of physicians and specialists for the sectors in question.

Investment process

Source: Bellevue Asset Management

Using a multi-stage process, the universe of around 1000 companies is systematically analyzed and evaluated. The use of artificial intelligence is being explored to deepen our knowledge and understanding. A detailed financial model is created for each investment, which must convincingly demonstrate the potential to double in value over a four-year period. This potential to double in value is based on innovative strength, new products for serious diseases and outstanding management. Each investment is systematically reviewed for sustainability risks and breaches of elementary human rights. Bellevue Asset Management AG is a signatory of UN Principles for Responsible Investment. Besides upholding strict exclusion criteria - such as serious controversies that violate universal norms regarding the environment, human rights or good corporate governance - environmental, social and governance factors are integrated into the fundamental analysis of every company through an ESG integration process in which the associated financial risks or opportunities are evaluated with respect to future stock market performance. The Investment Management Team strive to have an active and constructive dialogue with the management or other relevant stakeholders of the portfolio companies regarding environmental, social and governance aspects - and via proxy voting we use our voting rights actively at the general meetings.

With all of BB Biotech´s investments focusing on biotechnology as a subsector of the healthcare industry, the UN's Sustainable Development Goal number 3: "Good Health and Well-being", is at the core of BB Biotech's investment strategy and our portfolio companies. The investments of BB Biotech AG provide companies with capital in order to allow for drug development to ensure and improve healthy lives and well-being. Therapies to address high unmet medical needs such as for patients suffering from rare disorders, cancer, neurological diseases and chronic cardiovascular and metabolic disorders etc. are key investment selection criteria.

Before making a positive investment decision, intensive contact is established with the target company's management, since we are convinced that a superior performance can only be achieved with well managed companies.

After being incorporated into BB Biotech's portfolio, intense personal contact is maintained with members of the management of the relevant holdings. This closely knit monitoring of the portfolio companies enables BB Biotech to utilize all strategic options on a timely basis, including the early disposal of an equity interest should the fundamental situation significantly deteriorate.