Rare-Disease Biotech PTC Is Surging — And One Fund Just Raised Its Bet. Should You?

PTCT -3.48%

Key Points

• San Diego-based Tang Capital Management added 400,000 PTC Therapeutics shares in the third quarter.

• The value of the position increased by $38.3 million quarter over quarter.

• Tang Capital reported holding 1.5 million shares of PTCT valued at $92.1 million as of September 30.

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San Diego-based Tang Capital Management reported a $38.3 million increase in its stake in PTC Therapeutics (NASDAQ:PTCT) as of September 30, according to its latest SEC filing.

What Happened

Tang Capital disclosed in its November 14 Form 13-F filing that it increased its position in PTC Therapeutics (NASDAQ:PTCT) by 400,000 shares over the prior quarter. The fund’s holding rose to 1.5 million shares with a reported value of $92.1 million as of September 30. The quarter’s net position change in PTCT was $38.3 million.

What Else to Know

The buy helped raise PTCT to 3.5% of Tang's nearly $2.6 billion in reportable U.S. equity AUM, making it the fund’s fourth-largest holding.

Top holdings after the filing:

• NASDAQ: TARS: $145.9 million (5.6% of AUM)

• NASDAQ: GLPG: $143.8 million (5.5% of AUM)

• NASDAQ: AUPH: $125.2 million (4.8% of AUM)

• NASDAQ: PTCT: $92.1 million (3.5% of AUM)

• NASDAQ: MIRM: $90.6 million (3.5% of AUM)

As of Tuesday, shares of PTC Therapeutics were priced at $78.50, up 51% over the prior year and well outperforming the S&P 500, which is up 13% in the same period.

Company Overview

Metric

Value

Market Capitalization

$6.3 billion

Revenue (TTM)

$1.8 billion

Net Income (TTM)

$751.7 million

Price (as of market close Tuesday)

$78.50

Company Snapshot

• PTC Therapeutics commercializes rare disease therapies, including Translarna, Emflaza, Tegsedi, Waylivra, and Evrysdi, with a pipeline spanning clinical to pre-clinical stages focused on neuromuscular and genetic disorders.

• The company generates revenue primarily through the sale and licensing of proprietary pharmaceutical products and strategic collaborations with industry partners.

• It serves patients with rare and orphan diseases, targeting healthcare providers, specialty pharmacies, and government agencies across North America, Europe, Latin America, and select international markets.

PTC Therapeutics, Inc. is a mid-cap biopharmaceutical company specializing in the development and commercialization of innovative therapies for rare genetic disorders. The company leverages a diversified portfolio of approved products and a robust pipeline to address unmet medical needs in the rare disease space. Its strategic collaborations and global reach position it as a key player in the biotechnology sector focused on rare diseases.

Foolish Take

This latest move into PTC Therapeutics comes at a moment when the company is showing real commercial momentum—not just pipeline promise. The launch of Sephience is off to a strong start, and PTC has swung into profitability, giving investors fresh visibility into a business that has historically been volatile. For a stock sitting near all-time highs after major swings over the last decade, that combination of sustained growth and improving fundamentals is meaningful.According to a November 14 SEC filing, Tang Capital Management raised its position in PTC Therapeutics by 400,000 shares in the third quarter, boosting the value of its stake by $38.3 million. The fund now owns 1.5 million shares valued at $92.1 million, representing 3.5% of its nearly $2.6 billion reportable U.S. equity portfolio. That increase aligns with PTC’s accelerating fundamentals: Revenue climbed to $211 million in the third quarter, driven by $19.6 million in Sephience launch revenue and a surge in royalty income tied to Evrysdi. The company also swung to a quarterly net profit of $15.9 million, compared with a $106.7 million loss a year earlier.The takeaway here is that PTC’s growth is broadening, not relying solely on one franchise. Still, the stock’s extreme volatility—and a pipeline with regulatory risk—means any position should be sized with care.

Glossary

Stake: The ownership interest or investment a fund or individual holds in a company.Form 13-F: A quarterly SEC filing by institutional investment managers disclosing their equity holdings.AUM (Assets Under Management): The total market value of investments managed by a fund or investment firm.Reportable U.S. equity AUM: The portion of a fund’s assets invested in U.S. stocks that must be disclosed to regulators.Quarter over quarter: A comparison of financial or investment data from one fiscal quarter to the next.Holding: The amount of a particular security owned by an investor or fund.Outperforming: Achieving a higher return or better performance than a benchmark or index.Mid-cap: Refers to companies with a medium-sized market capitalization, typically between $2 billion and $10 billion.Rare disease therapies: Treatments developed for diseases affecting a small percentage of the population, often called orphan diseases.Pipeline: The set of drug candidates a pharmaceutical company is developing, from pre-clinical to clinical stages.Strategic collaborations: Partnerships between companies to jointly develop, market, or distribute products or technologies.TTM: The 12-month period ending with the most recent quarterly report.

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Jonathan Ponciano has no position in any of the stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. The Motley Fool has a disclosure policy.

Rare-Disease Biotech PTC Is Surging — And One Fund Just Raised Its Bet. Should You? was originally published by The Motley Fool