A month has gone by since the last earnings report for Prothena (PRTA Quick QuotePRTA - Free Report) . Shares have added about 17.6% in that time frame, outperforming the S&P 500.

Will the recent positive trend continue leading up to its next earnings release, or is Prothena due for a pullback? Before we dive into how investors and analysts have reacted as of late, let's take a quick look at its latest earnings report in order to get a better handle on the important catalysts.

Prothena Q2 Earnings Miss Estimates, Focus on Key Readouts in 2025

ProthenaCorporation reported second-quarter 2025 adjusted loss per share (excluding restructuring costs) of $1.86, much wider than the Zacks Consensus Estimate of a loss of $1.11. In the year-ago quarter, the company posted an earnings of $1.22 boosted by higher collaboration revenue.

Revenues totaled $4.4 million, which missed the Zacks Consensus Estimate of $21 million. Prothenarecorded revenues of $132 million.

Q2 Results in Detail

Research and development (R&D) expenses decreased 29.5% year over year to $40.5 million, primarily due to due to lower clinical trial expenses, lower manufacturing and lower personnel expenses.

General and administrative expenses amounted to $15.9 million, down from $16.1 million in the year-ago quarter.

As of June 30, 2025, Prothenahad $372.3 million in cash, cash equivalents and restricted cash, and no debt.

Pipeline Updates

The company is also evaluating prasinezumab, in collaboration with Roche for the treatment of Parkinson’s disease (PD).

Partner Roche will advance advanceprasinezumabinto phase III development for early-stage Parkinson's disease with initiation expected by the end of 2025.

Roche is currently conducting the Open Label Extensions (OLEs) of the phase II PASADENA and phase IIb PADOVA clinical studies.

Prothenais evaluating PRX012 — a wholly owned single-injection once-monthly antibody delivered subcutaneously targeting a key epitope at the N-terminus of amyloid beta (Aβ) — for treating Alzheimer’s Disease (AD). The FDA has granted Fast Track designation to PRX012 for the treatment of Alzheimer’s disease. Prothena expects to report initial data from the phase I ASCENT clinical trials shortly.

Prothena is advancing an early-stage pipeline of programs for several potential neurological indications with Bristol Myers.

BMS-986446 (formerly PRX005) is a best-in-class anti-tau, MTBR-specific antibody for the potential treatment of AD.

Bristol Myers is conducting the phase II TargetTau-1 study in approximately 310 patients with early Alzheimer’s disease and primary completion expected in 2027. Bristol Myers Squibb is also conducting a phase I open-label single-dose clinical trial to assess a subcutaneous administration; primary completion expected in the second half of 2025.

PRX019, a potential treatment for neurodegenerative diseases, is also being developed in collaboration with Bristol Myers, which obtained the exclusive global license for the candidate in 2024. Prothena has initiated a phase I first-in-human clinical trial on PRX019 to evaluate the safety, tolerability, immunogenicity, and pharmacokinetics of single ascending and multiple doses in healthy adults. The phase I study is expected to be completed in 2026.

Prothena is also developing a dual Aβ-Tau vaccine, PRX123, which is a potential preventive and therapeutic treatment for AD. It is a dual-target vaccine targeting key epitopes within the N-terminus of Aβ and MTBR-tau, designed to promote amyloid clearance and block the transmission of pathogenic tau. The FDA has cleared an Investigational New Drug Application for PRX123.

The regulatory body granted Fast Track designation to PRX123 for the treatment of AD. However, Prothena expects to advance PRX123 through non-dilutive and capital efficient structures.

Novo Nordisk had earlier acquired Prothena’s clinical-stage antibody, Coramitug (formerly PRX004), a potential first-in-class amyloid depleter antibody for the treatment of ATTR amyloidosis with cardiomyopathy.

Novo Nordisk completed a phase II study in patients with ATTR cardiomyopathy. Results are expected in the second half of 2025. Coramitug is also being evaluated in an ongoing open label extension trial for participants who completed the phase II study.

Reiterates 2025 Guidance

The company expects 2025 net cash burn from operating and investing activities to be in the range of $170 to $178 million. It expects year-end cash, cash equivalents and restricted cash midpoint to be approximately $298 million. Net loss for 2025 is projected to be in the $240 to $248 million million range.

How Have Estimates Been Moving Since Then?

Since the earnings release, investors have witnessed a upward trend in estimates review.

The consensus estimate has shifted 29.35% due to these changes.

VGM Scores

Currently, Prothena has a average Growth Score of C, however its Momentum Score is doing a lot better with an A. However, the stock has a score of F on the value side, putting it in the bottom 20% quintile for value investors.

Overall, the stock has an aggregate VGM Score of D. If you aren't focused on one strategy, this score is the one you should be interested in.

Outlook

Estimates have been trending upward for the stock, and the magnitude of these revisions looks promising. Interestingly, Prothena has a Zacks Rank #3 (Hold). We expect an in-line return from the stock in the next few months.

Performance of an Industry Player

Prothena belongs to the Zacks Medical - Biomedical and Genetics industry. Another stock from the same industry, Amarin (AMRN Quick QuoteAMRN - Free Report) , has gained 0.3% over the past month. More than a month has passed since the company reported results for the quarter ended June 2025.

Amarin reported revenues of $72.74 million in the last reported quarter, representing a year-over-year change of +7.8%. EPS of -$0.03 for the same period compares with $0.20 a year ago.

Amarin is expected to post a loss of $0.68 per share for the current quarter, representing a year-over-year change of +32%. Over the last 30 days, the Zacks Consensus Estimate remained unchanged.

The overall direction and magnitude of estimate revisions translate into a Zacks Rank #3 (Hold) for Amarin. Also, the stock has a VGM Score of B.