Shares of Janux Therapeutics JANX surged 49% on Tuesday after the company posted updated interim results from a phase Ib study, which is evaluating JANX007 in patients with advanced or metastatic prostate cancer (mCRPC).

The study enrolled mCRPC patients who were heavily pretreated with a median of four prior lines of therapy. As of the cut-off date of Nov. 15, 2024, 16 patients had been treated with once-weekly JANX007 doses ranging from 2 mg to 9 mg. None of these patients had been treated with Pluvicto, Novartis’ blockbuster prostate cancer therapy.

Data from the study showed that after 12 weeks of treatment with JANX007, all 16 patients achieved a 50% decline in prostate-specific antigen (PSA). PSA is a protein produced by cells of the prostate gland, too much of which is an indication of cancer. Treatment with the drug also demonstrated a favorable safety profile.

Of the 16 patients, 10 achieved a 90% reduction in PSA levels, with five experiencing a decline of 99%. Management also highlighted the sustained PSA reductions, noting that 75% of patients with a 50% decline maintained it for at least 12 weeks. Similarly, 50% of patients who achieved a 90% PSA decline maintained their reductions for the same duration.

Based on the above results, two once-weekly step-dose regimens of JANX007 have been selected for phase Ib expansion studies. These studies will enroll previously treated mCRPC patients who are yet to receive Pluvicto. Janux expects to provide an update on the drug next year.

JANX Stock’s Performance

Following the news, shares of Janux hit an all-time high of $71.25. Wall Street has been paying a lot of attention to the stock, thanks to the impressive clinical performance of JANX007. Management had previously provided an update on the above study earlier in February, where it claimed that 56% of the study participants who received the drug achieved a decline of 50% in PSA levels.

With this latest announcement, investors were likely impressed as the company’s drug efficacy surpassed the company’s last reported data. Several Wall Street analysts also praised the results, one even calling it ‘unprecedented.’ This is a likely reason for the share price soaring to an all-time high.

Year to date, Janux Therapeutics’ shares have soared 457.9% against the industry’s 7.0% decline.

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Why VIR Stock Rose on JANX News

Post Janux’s encouraging update on JANX007, shares of Vir Biotechnology (VIR) also rose 13% on Tuesday. Vir is also developing VIR-5500, a drug that is similar to JANX007.

VIR-5500 is currently being evaluated in an early-stage dose escalation study in mCRPC patients. Vir Biotechnology expects to provide an update in the first quarter of 2025.

JANX’s Zacks Rank

Janux Therapeutics currently carries a Zacks Rank #4 (Sell).

Janux Therapeutics, Inc. Price

Janux Therapeutics, Inc. price | Janux Therapeutics, Inc. Quote

Key Picks Among Biotech Stocks

A couple of better-ranked stocks from the sector are Castle Biosciences CSTL and Spero Therapeutics SPRO, each sporting a Zacks Rank #1 (Strong Buy) at present. You can see the complete list of today’s Zacks #1 Rank stocks here.

In the past 60 days, estimates for Castle Biosciences’ 2024 loss per share have narrowed from 58 cents to 8 cents. During the same timeframe, loss per share estimates for 2025 have narrowed from $2.13 to $1.88. Year to date, shares of Castle Biosciences have surged 42.6%.

CSTL’s earnings beat estimates in each of the trailing four quarters, delivering an average surprise of 172.72%.

In the past 60 days, estimates for Spero Therapeutics’ 2024 loss per share have narrowed from $1.59 to $1.13. Estimates for 2025 loss per share have narrowed from $1.54 to 54 cents. Year to date, shares of Spero Therapeutics have lost 21.1%.

Spero Therapeutics’ earnings beat estimates in two of the trailing four quarters and missed the mark in the other two, delivering an average surprise of 94.42%.

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