The Telix Pharmaceuticals Ltd (ASX: TLX) share price is taking a beating today.

Shares in the S&P/ASX 200 Index (ASX: XJO) diagnostic and therapeutic product developer closed yesterday trading for $25.12. In earlier trade, shares plunged to $21.00 apiece, down a precipitous 16.4%.

After some likely bargain hunting, shares are currently changing hands for $22.41 apiece, down 10.8%.

Here's what's got investors hitting their sell buttons today.

Telix share price hit by US subpoena

The Telix share price has come under heavy selling pressure today amid news the company has been issued with a subpoena from the United States Securities and Exchange Commission (SEC).

As the company reported after market close yesterday, the subpoena involves disclosures related to Telix's prostate cancer therapies.

Labelling the SEC move a "fact-finding request", the ASX 200 pharmaceutical company said, "We cannot predict when this matter will be resolved or what (if any) action the SEC may take following the conclusion of its investigation."

The Telix share price looks to be avoiding heavier losses, with the company noting that the SEC investigation involves its "prostate cancer therapeutic candidates". Telix said this will not affect its commercial or late-stage products, like its core revenue earner, cancer imaging drug Illuccix.

While the matter is ongoing, Telix said it will continue with its clinical development programs relating to its prostate cancer therapy candidates.

What else is impacting the Telix share price?

If not for the SEC subpoena, the Telix share price likely would be enjoying a boost today following the company's quarterly update (Q2 2025), also released after market close on Tuesday.

Highlights for the three months to 30 June included a 63% year-on-year increase in unaudited revenue to approximately US$204 million.

The June quarter saw Telix receive country-level approvals for Illuccix in France, Finland, Ireland, Sweden, Germany, Portugal, Greece, the Czech Republic, Belgium, and Italy. The company said it is launching into the new nations on a market-by-market basis, as reimbursement is secured.

Telix also reaffirmed its full year FY 2025 revenue guidance of US$770 million to US$800 million.

What did management say?

Commenting on the quarterly results that have yet to boost the Telix share price, CEO Christian Behrenbruch said, "Dose volumes for Illuccix rose 7% quarter-on-quarter in the US, reinforcing the strength of our market position and continued customer demand."

Behrenbruch added:

Despite emerging competitive pricing pressure, we have effective strategies in place to manage impact to average selling price. This includes the recent launch of Gozellix which has been assigned a HCPCS code, a crucial reimbursement milestone towards pass through status.

We continue to show positive momentum across multiple assets in our therapeutic pipeline, including achievement of a key recruitment milestone in our ProstACT Global Phase 3 trial.

With today's steep intraday loss factored in, the Telix share price remains up just over 10% since this time last year.