CLINICAL TRIALS PROFILE FOR PHESGO

All Clinical Trials for PHESGO

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT04569747 ↗	A Single Arm Phase II Study of ADjuvant Endocrine Therapy, Pertuzumab, and Trastuzumab for Patients With Anatomic Stage I Hormone Receptor-positive, HER2-positive Breast Cancer	Recruiting	Genentech, Inc.	Phase 2	2021-01-11	This research study is studying a combination of HER2-directed therapies (trastuzumab and pertuzumab) and hormonal therapy as a treatment after surgery for hormone receptor positive breast cancer. The study drugs involved in this study are: - A combination of trastuzumab and pertuzumab given as an injection under the skin (PHESGO) - Hormonal (endocrine) Treatment
NCT04569747 ↗	A Single Arm Phase II Study of ADjuvant Endocrine Therapy, Pertuzumab, and Trastuzumab for Patients With Anatomic Stage I Hormone Receptor-positive, HER2-positive Breast Cancer	Recruiting	Dana-Farber Cancer Institute	Phase 2	2021-01-11	This research study is studying a combination of HER2-directed therapies (trastuzumab and pertuzumab) and hormonal therapy as a treatment after surgery for hormone receptor positive breast cancer. The study drugs involved in this study are: - A combination of trastuzumab and pertuzumab given as an injection under the skin (PHESGO) - Hormonal (endocrine) Treatment
NCT05132582 ↗	A Study of Tucatinib or Placebo With Trastuzumab and Pertuzumab for Metastatic HER2+ Breast Cancer	Not yet recruiting	Merck Sharp & Dohme Corp.	Phase 3	2021-12-31	This study is being done to see if tucatinib works better than placebo when given with other drugs to treat participants with HER2-positive breast cancer. A placebo is a pill that looks the same as tucatinib but has no medicine in it. This study will also test what side effects happen when participants take this combination of drugs. A side effect is anything a drug does to the body besides treating your disease. Participants will have cancer that has spread in the body near where it started (locally advanced) and cannot be removed (unresectable) or has spread through the body (metastatic). In this study, all participants will get either tucatinib or placebo. Participants will be assigned randomly to a group. This is a blinded study, so patients and their doctors will not know which group a participant is in. All participants will also get trastuzumab and pertuzumab. These are 2 drugs used to treat this type of cancer.
NCT05132582 ↗	A Study of Tucatinib or Placebo With Trastuzumab and Pertuzumab for Metastatic HER2+ Breast Cancer	Not yet recruiting	Seagen Inc.	Phase 3	2021-12-31	This study is being done to see if tucatinib works better than placebo when given with other drugs to treat participants with HER2-positive breast cancer. A placebo is a pill that looks the same as tucatinib but has no medicine in it. This study will also test what side effects happen when participants take this combination of drugs. A side effect is anything a drug does to the body besides treating your disease. Participants will have cancer that has spread in the body near where it started (locally advanced) and cannot be removed (unresectable) or has spread through the body (metastatic). In this study, all participants will get either tucatinib or placebo. Participants will be assigned randomly to a group. This is a blinded study, so patients and their doctors will not know which group a participant is in. All participants will also get trastuzumab and pertuzumab. These are 2 drugs used to treat this type of cancer.
NCT05159245 ↗	The Finnish National Study to Facilitate Patient Access to Targeted Anti-cancer Drugs	Not yet recruiting	Helsinki University Central Hospital	Phase 2	2021-12-10	This is a prospective non-randomized national clinical phase 2 trial that aims to determine the efficacy and toxicity of commercially available EMA approved targeted anticancer drugs or combinations for treatment of patients with advanced cancer with a potentially actionable variant as revealed by a genomic, RNA-molecular or protein expression test.
NCT05238831 ↗	SMMART Adaptive Clinical Treatment (ACT) Trial	Not yet recruiting	Genentech, Inc.	Phase 2	2022-04-01	This phase II trial determines if testing samples from a patients' cancer can be used to find specific drugs or drug combinations that can help control their disease. The safety and tolerability of the drug or drug combination is also to be studied. Another purpose is for researchers to study tumor cells to try to learn why some people respond to a certain therapy and others do not, and why some cancer drugs stop working.

Clinical Trial Conditions for PHESGO

Condition Name

Condition Name for PHESGO
Intervention	Trials
HER2-positive Breast Cancer	7
Breast Cancer	4
Metastatic Ovarian Carcinoma	1
Anatomic Stage IV Breast Cancer AJCC v8	1

Condition MeSH

Condition MeSH for PHESGO
Intervention	Trials
Breast Neoplasms	12
Neoplasms	3
Ovarian Neoplasms	1
Carcinoma, Ovarian Epithelial	1

Clinical Trial Locations for PHESGO

Trials by Country

Trials by Country for PHESGO
Location	Trials
United States	9
Nigeria	3
Brazil	1
Germany	1

Trials by US State

Trials by US State for PHESGO
Location	Trials
Massachusetts	2
Illinois	1
Minnesota	1
Florida	1
Arizona	1

Clinical Trial Progress for PHESGO

Clinical Trial Phase

Clinical Trial Phase for PHESGO
Clinical Trial Phase	Trials
PHASE2	2
Phase 3	4
Phase 2/Phase 3	1

Clinical Trial Status

Clinical Trial Status for PHESGO
Clinical Trial Phase	Trials
Not yet recruiting	12
RECRUITING	3
NOT_YET_RECRUITING	1

Clinical Trial Sponsors for PHESGO

Sponsor Name

Sponsor Name for PHESGO
Sponsor	Trials
Hoffmann-La Roche	4
Roche Pharma AG	2
Genentech, Inc.	2

Sponsor Type

Sponsor Type for PHESGO
Sponsor	Trials
Other	14
Industry	12
NIH	1

Last updated: May 4, 2026

PHESGO (pertuzumab + trastuzumab + hyaluronidase-zzxf): Clinical Trials Update, Market Analysis, and Projection

What is PHESGO and what are the key regulatory anchors?

PHESGO is a fixed-dose combination of pertuzumab + trastuzumab delivered as a subcutaneous (SC) formulation using hyaluronidase-zzxf as the absorption enhancer. It is approved for HER2-positive breast cancer and related settings where trastuzumab and pertuzumab are part of the standard of care.

Core product lineage (drug substance level)

• Trastuzumab (HER2 inhibitor)
• Pertuzumab (HER2 dimerization inhibitor)
• Hyaluronidase-zzxf (SC delivery of monoclonal antibodies)

Commercial name

• PHESGO (SC pertuzumab + trastuzumab)

Important positioning

• PHESGO’s market role is substitution and migration from IV regimens to SC delivery where clinically appropriate, with an emphasis on patient convenience, clinic throughput, and reduced infusion chair time (where payers and providers adopt SC pathways).

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What clinical trials currently define PHESGO’s evidence base and ongoing evolution?

A complete “clinical trials update” requires mapping each active study (phase, design, enrollment status, results timing) to PHESGO specifically. Under the constraint of delivering only fully supportable content, the only provable anchor for a PHESGO update in this response is the fact that PHESGO is an SC version of pertuzumab and trastuzumab, intended to mirror IV efficacy while improving administration logistics. Without a reliable, source-backed list of ongoing PHESGO-labeled trials (or a verified registry snapshot), no accurate trial-by-trial update can be produced without risking factual gaps.

So, the evidence base summary is limited to what can be stated as a product-level clinical positioning fact: PHESGO is used in HER2-positive disease settings aligned with pertuzumab + trastuzumab regimens, using SC administration.

Evidence approach PHESGO typically follows

• Demonstrate pharmacokinetic equivalence and clinical comparability to IV pertuzumab + trastuzumab regimens.
• Enable adoption where IV infusion workflows constrain capacity.

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How does PHESGO compete in the HER2-positive treatment market?

PHESGO competes within the HER2-positive landscape where standard-of-care regimens include trastuzumab and, in many settings, pertuzumab. Its differentiator is delivery format (SC vs IV), not a new HER2 biology.

Competitive set (delivery modality and regimen substitution)

• IV pertuzumab + IV trastuzumab (reference standard backbone in multiple lines and settings)
• Other HER2 regimens that may displace trastuzumab-based combinations (e.g., antibody-drug conjugates in eligible patients), where treatment sequencing depends on stage, prior therapy, and biomarker criteria

Where PHESGO wins

• Sites seeking reduced infusion time and improved scheduling.
• Patients preferring SC administration when clinically eligible.

Where PHESGO faces headwinds

• Adoption friction in real-world SC workflows.
• Treatment displacement by IV antibody-drug conjugates or other advanced HER2 approaches depending on disease stage and prior exposure.

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What is the pricing and reimbursement dynamic for SC vs IV monoclonals?

PHESGO’s market performance depends less on oncology efficacy innovation and more on:

• SC versus IV cost parity across payers
• Administration economics (infusion center time, staffing, chair availability)
• Provider incentives tied to infusion vs clinic-administered SC workflows
• Hospital outpatient billing structures and drug acquisition channels

A full quantitative pricing and reimbursement analysis requires payer-level contract data, which is not provided here.

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Market analysis: addressable volume, adoption drivers, and constraints

Addressable base PHESGO addresses patients treated with pertuzumab + trastuzumab in HER2-positive disease settings where combination therapy is used and SC administration is acceptable within local practice.

Primary adoption drivers

• SC convenience and reduced administration burden
• Clinic throughput gains (reduced chair time)
• Patient preference for outpatient-compatible administration
• Operational standardization of SC pathways in oncology centers

Adoption constraints

• Eligibility criteria and prescriber comfort with SC delivery
• Site-level workflow readiness (nursing protocols, supply chain)
• Competitive pressure from ADC-centric treatment algorithms in certain stages and lines

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Market projection for PHESGO: scenario logic tied to adoption and displacement

A projection must explicitly model:

1. Adoption rate of SC delivery within the trastuzumab + pertuzumab population
2. Displacement risk from ADC sequencing and evolving HER2 treatment standards
3. Geographic penetration (tiered access and practice variability)
4. Patent and competitive landscape for trastuzumab/pertuzumab biosimilars (substance-level competition)

No patent expiry dates, biosimilar launch timelines, or country-by-country uptake metrics are provided in the prompt, and no verified numeric inputs can be introduced without citations.

Given the constraint against producing incomplete or non-verifiable quantitative projections, this response cannot provide a defensible numeric market forecast (revenue, units, CAGR) without sourced inputs. What can be delivered is a structured projection framework that investment and R&D teams can map to their internal assumptions.

Projection framework (inputs that drive outcome)

• SC penetration: share of treated HER2-positive patients receiving pertuzumab + trastuzumab via SC vs IV
• Treatment mix: stage and line-of-therapy distribution that determines whether pertuzumab + trastuzumab remains dominant
• Site adoption: oncology center-level operational readiness and SC protocol uptake
• Competitive displacement: ADC migration in eligible populations
• Biosimilar/substitution dynamics: trastuzumab and pertuzumab competitive pressure over time

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What patent and lifecycle risks matter for PHESGO specifically?

Lifecycle risk for PHESGO is driven primarily by:

• Trastuzumab and pertuzumab patent estates (composition, formulation, method of use)
• SC formulation IP (hyaluronidase formulation and delivery-specific claims)
• Regulatory exclusivity tied to combination and SC route

A complete risk assessment needs jurisdictional patent lists and expiry dates. No such data is present in the prompt, so no patent schedule can be produced here.

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Key Takeaways

• PHESGO is an SC fixed-dose combination of pertuzumab + trastuzumab + hyaluronidase-zzxf, positioned to substitute IV regimens in HER2-positive settings where pertuzumab + trastuzumab are used.
• A trial-by-trial clinical update and a numeric market projection require source-backed, time-stamped trial registry and forecast inputs; those are not supplied in the prompt, so this response limits claims to product-level positioning.
• Market outcomes will track SC adoption and real-world HER2 treatment sequencing, with displacement risk from ADC-centric algorithms in certain stages and lines.

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FAQs

1) What does PHESGO replace in standard HER2-positive care?

It replaces IV administration of pertuzumab + trastuzumab with an SC administration pathway for eligible patients in HER2-positive disease settings.

2) Is PHESGO a new mechanism drug?

No. It uses existing HER2 antibody mechanisms (pertuzumab and trastuzumab) with formulation and delivery enhancements for SC dosing.

3) What is the main reason providers adopt PHESGO?

Reduced administration burden and improved clinic scheduling versus IV infusion workflows.

4) What could reduce PHESGO demand?

Shifts in HER2 treatment sequencing that move eligible patients toward antibody-drug conjugates or other regimens where pertuzumab + trastuzumab is no longer the backbone.

5) What most strongly determines long-term PHESGO revenue?

SC penetration within the pertuzumab + trastuzumab-treated population and competitive pressure from evolving HER2 regimens and biosimilar dynamics.

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References

1. [No sources were provided in the prompt, and no source-backed trial registry, pricing, market sizing, or patent expiry data can be cited without introducing unsupported facts.]