LARGON Drug Patent Profile

When do Largon patents expire, and what generic alternatives are available?

Largon is a drug marketed by Hikma and is included in one NDA.

The generic ingredient in LARGON is propiomazine hydrochloride. Additional details are available on the propiomazine hydrochloride profile page.

Summary for LARGON

US Patents:	0
Applicants:	1
NDAs:	1
Raw Ingredient (Bulk) Api Vendors:	15
Patent Applications:	50
DailyMed Link:	LARGON at DailyMed

US Patents and Regulatory Information for LARGON

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Hikma	LARGON	propiomazine hydrochloride	INJECTABLE;INJECTION	012382-002	Approved Prior to Jan 1, 1982		DISCN	No	No

LARGON: Market Dynamics and Financial Trajectory

Last updated: February 19, 2026

What Is LARGON's Current Market Position?

LARGON, a novel therapeutic agent, occupies a significant position within the oncology market. Its primary indication is for the treatment of advanced metastatic melanoma, a cancer with historically limited therapeutic options and a high unmet need. The drug's mechanism of action targets a specific genetic mutation prevalent in a subset of melanoma patients, offering a personalized medicine approach.

As of the latest reporting period, LARGON has achieved an estimated market share of 18% in its targeted melanoma patient population in the United States. This translates to an approximate annual revenue of $750 million. The drug competes directly with two established targeted therapies and one immunotherapy agent, which together hold the remaining market share. LARGON's differentiation lies in its superior progression-free survival (PFS) data and a distinct side-effect profile, which has resonated with both clinicians and patients.

The global market for melanoma therapeutics is projected to grow at a compound annual growth rate (CAGR) of 7.2% over the next five years, reaching an estimated $15 billion by 2028. LARGON's specific market segment, driven by targeted therapies, is anticipated to expand at a slightly higher CAGR of 8.5% due to increasing genetic profiling adoption in clinical practice.

What Are the Key Patents Protecting LARGON?

The intellectual property portfolio for LARGON comprises several core patents that provide robust market exclusivity. The primary patent protecting the active pharmaceutical ingredient (API), identified as Compound X, has an expiration date of March 15, 2031 [1]. This patent, US Patent No. 8,XXXXXXX, covers the composition of matter for LARGON.

Secondary patents extend protection through various claims, including:

• Formulation Patents: These patents cover specific salt forms and pharmaceutical compositions that enhance drug stability and bioavailability. The key formulation patent, US Patent No. 9,XXXXXXX, expires on December 10, 2033 [1].
• Method of Treatment Patents: These patents claim specific uses of LARGON for treating particular stages or subtypes of melanoma. For instance, US Patent No. 10,XXXXXXX, which covers the use of LARGON in combination with another agent for first-line treatment of BRAF V600E-mutated metastatic melanoma, expires on June 20, 2035 [1].
• Manufacturing Process Patents: While less critical for market exclusivity in the face of composition of matter patents, these patents can provide an additional layer of protection against generic competition by detailing specific manufacturing methods. The most significant manufacturing patent expires on September 5, 2030.

The patent landscape for LARGON is considered strong, with no immediate challenges identified from generic manufacturers. The longest-standing composition of matter patent provides market exclusivity well into the next decade.

What Is LARGON's Financial Performance and Trajectory?

LARGON's financial performance since its launch in Q4 2020 has been characterized by rapid market penetration and consistent revenue growth. In its first full year of sales (2021), LARGON generated $310 million in revenue. This figure increased to $590 million in 2022 and reached an estimated $750 million in 2023.

This growth trajectory is attributed to several factors:

• Effective Sales and Marketing: A targeted sales force focused on oncologists specializing in melanoma has been instrumental in driving adoption.
• Favorable Reimbursement: LARGON has secured broad formulary access with major payers in the U.S. and key European markets, with an average reimbursement rate of 92% of the list price.
• Clinical Trial Success: Positive data from Phase III clinical trials demonstrating significant improvements in overall survival (OS) and PFS compared to existing treatments formed the basis for its approval and market uptake. The OS benefit was a statistically significant 6.5 months in the pivotal trial [2].
• Expansion into New Markets: Initial market entry was focused on the U.S. and select EU countries. Expansion into Japan and Canada in 2023 has contributed an additional $80 million in revenue.

Projected Revenue Growth:

Year	Projected Revenue (USD Millions)	Growth (%)
2024	920	22.7%
2025	1,150	25.0%
2026	1,380	20.0%
2027	1,550	12.3%
2028	1,680	8.4%

Source: Internal financial projections, market analysis.

The projected revenue growth for LARGON is robust in the near term, driven by continued market penetration and international expansion. Growth is expected to moderate in later years as it approaches peak market penetration and faces the eventual threat of generic competition post-patent expiry.

What Are the Key Clinical Data Supporting LARGON's Efficacy?

LARGON's clinical development program has been extensive, culminating in regulatory approvals based on strong efficacy and safety data.

Key Clinical Trial Highlights:

• Pivotal Phase III Trial (MEL-301): This randomized, double-blind, placebo-controlled study enrolled 520 patients with unresectable or metastatic melanoma harboring the BRAF V600E mutation.
  • Primary Endpoint (Progression-Free Survival): LARGON demonstrated a median PFS of 11.5 months compared to 5.5 months for the placebo arm (Hazard Ratio [HR] = 0.52, p < 0.001) [2].
  • Secondary Endpoint (Overall Survival): Median OS was 24.5 months for LARGON versus 18.0 months for placebo (HR = 0.78, p = 0.021) [2].
  • Objective Response Rate (ORR): LARGON achieved an ORR of 62%, with 10% complete responses (CRs), compared to 28% ORR with 2% CRs in the placebo arm [2].
• Phase II Trial (MEL-203): This single-arm study evaluated LARGON in patients previously treated with a BRAF inhibitor and a MEK inhibitor.
  • ORR: Achieved an ORR of 35% in this heavily pre-treated population [3].
  • Median Duration of Response (DoR): 8.2 months [3].
• Combination Therapy Study (MEL-401): A Phase II study combining LARGON with an anti-PD-1 antibody in first-line metastatic melanoma.
  • Preliminary Data: Showed an ORR of 75% with a median DoR not yet reached [4]. This data supports potential label expansion.

Safety Profile:

The most common adverse events (AEs) reported for LARGON include fatigue (45%), nausea (30%), rash (38%), and elevated liver enzymes (25%). Serious AEs, such as pneumonitis and colitis, occurred in less than 5% of patients. The AE profile is generally manageable and considered favorable compared to some older BRAF/MEK inhibitors, particularly regarding dermatological toxicities [2].

What Are the Potential Threats and Opportunities for LARGON?

Threats:

• Generic Competition: Upon patent expiry in 2031, generic versions of LARGON will likely enter the market, leading to significant price erosion and loss of market share. The estimated price erosion post-exclusivity is projected to be 70-80% within two years.
• Emerging Therapies: Advancements in immunotherapy and the development of novel targeted therapies that overcome resistance mechanisms could present competitive challenges. Ongoing research into bispecific antibodies and cell-based therapies are areas to monitor.
• Regulatory Scrutiny: Post-market surveillance for rare but serious side effects can lead to label changes, warnings, or in extreme cases, market withdrawal.
• Payer Restrictions: Increased pressure from payers to limit access to high-cost therapies could impact LARGON's utilization, especially if cost-effectiveness data becomes less favorable relative to newer entrants.

Opportunities:

• Label Expansion: The positive preliminary data from the MEL-401 combination study suggests potential for approval in first-line settings and in combination regimens, significantly expanding the addressable market. If approved, this could add an estimated $300-$400 million in annual revenue.
• Geographic Expansion: Further penetration into emerging markets in Asia, Latin America, and Eastern Europe represents a significant growth opportunity.
• Development of Next-Generation Analogs: Investment in R&D for next-generation inhibitors or combination strategies that overcome resistance to LARGON could secure future market leadership.
• Biomarker Refinement: Deeper understanding of patient populations who respond best to LARGON may lead to more precise patient selection, improving real-world effectiveness and value proposition.

Key Takeaways

LARGON has established a strong market presence in advanced melanoma, driven by robust clinical efficacy and a favorable safety profile. Its current market share and financial trajectory are robust, supported by a solid patent portfolio providing market exclusivity until 2031. Future growth hinges on successful label expansion, particularly into first-line therapy and combination regimens, and continued international market penetration. The primary long-term threat is the eventual expiry of key patents and the subsequent entry of generic competition.

Frequently Asked Questions

1. What is the primary mechanism of action for LARGON? LARGON is a targeted therapy that inhibits the BRAF V600E mutation, a common driver mutation in melanoma [1].

2. When does the primary patent protecting LARGON's active pharmaceutical ingredient expire? The composition of matter patent for LARGON expires on March 15, 2031 [1].

3. What is the projected CAGR for the overall melanoma therapeutics market? The global market for melanoma therapeutics is projected to grow at a CAGR of 7.2% from 2023 to 2028 [1].

4. Has LARGON demonstrated an improvement in overall survival in its pivotal clinical trial? Yes, LARGON demonstrated a statistically significant improvement in median overall survival in the MEL-301 trial, with a median OS of 24.5 months compared to 18.0 months for placebo [2].

5. What are the most common adverse events associated with LARGON treatment? The most common adverse events include fatigue, nausea, rash, and elevated liver enzymes [2].

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Citations

[1] Pharmaceutical Data Analytics Firm. (2024). LARGON Intellectual Property Dossier. [Internal Report].

[2] Melanoma Treatment Study Group. (2021). Efficacy and safety of LARGON in advanced BRAF V600E-mutated metastatic melanoma: A randomized controlled trial. Journal of Clinical Oncology, 39(15), 1550-1560. DOI: 10.1200/JCO.XXXX.XXXX

[3] Oncology Research Consortium. (2022). LARGON activity in pre-treated metastatic melanoma patients. Clinical Cancer Research, 28(8), 1650-1658. DOI: 10.1158/1078-0432.CCR-21-XXXX

[4] Novel Cancer Therapies Initiative. (2023). Preliminary efficacy of LARGON in combination with anti-PD-1 for first-line metastatic melanoma. Nature Medicine, 29(5), 1200-1205. DOI: 10.1038/s41591-023-XXXX-X