List of Excipients in Branded Drug RUBRACA

Company	Tradename	Ingredient	NDC	Excipient	Potential Generic Entry
Clovis Oncology Inc	RUBRACA	rucaparib	69660-201	CELLULOSE, MICROCRYSTALLINE	2035-08-17
Clovis Oncology Inc	RUBRACA	rucaparib	69660-201	FD&C BLUE NO. 1	2035-08-17
Clovis Oncology Inc	RUBRACA	rucaparib	69660-201	FD&C BLUE NO. 2	2035-08-17
Clovis Oncology Inc	RUBRACA	rucaparib	69660-201	MAGNESIUM STEARATE	2035-08-17

Rubraca Excipient Strategy, Formulation Patents, and Commercial Opportunities

Last updated: August 22, 2026

Rubraca is the oral PARP inhibitor rucaparib camsylate, marketed as immediate-release film-coated tablets in 200 mg, 250 mg, and 300 mg strengths. Its commercial formulation uses a conventional direct-compression or high-shear tablet platform with a relatively low-cost excipient system. The strongest commercial opportunities are in generic formulation development, excipient substitution, regional supply, drug-product manufacturing, and differentiated oral delivery systems rather than in a simple copy of the reference tablet.

What is Rubraca and how is it formulated?

Rubraca contains rucaparib camsylate, a salt form of the active pharmaceutical ingredient used to improve drug-product handling and oral delivery. The FDA-approved product is supplied as immediate-release tablets and is dosed at 600 mg orally twice daily in approved indications.[1]

Product attribute	Rubraca profile
Active ingredient	Rucaparib camsylate
Brand	Rubraca
Dosage form	Immediate-release film-coated tablet
Strengths	200 mg, 250 mg, 300 mg
Typical adult dose	600 mg twice daily, subject to indication and tolerability
Administration	With or without food
Original developer	Clovis Oncology
Therapeutic class	PARP inhibitor
Main use	Maintenance treatment in selected ovarian, fallopian tube, and primary peritoneal cancers
Additional historical use	Selected metastatic castration-resistant prostate cancer patients
FDA pathway	NDA approval, including accelerated approvals for certain indications

The three strengths allow dose modification without requiring tablet splitting. The 300 mg tablet is particularly important commercially because the standard 600 mg dose requires two tablets per administration.

What excipients are used in Rubraca tablets?

The Rubraca tablet platform uses common oral solid-dose excipients. The FDA prescribing information identifies tablet-core and film-coating ingredients including microcrystalline cellulose, sodium starch glycolate, colloidal silicon dioxide, magnesium stearate, polyvinyl alcohol, titanium dioxide, polyethylene glycol, talc, and colorants.[1]

Formulation function	Rubraca excipient examples	Commercial role
Diluent and compression aid	Microcrystalline cellulose	Tablet mass, compactability, mechanical strength
Disintegrant	Sodium starch glycolate	Rapid tablet breakup and dissolution
Glidant	Colloidal silicon dioxide	Powder flow and content uniformity
Lubricant	Magnesium stearate	Ejection from tablet tooling
Film former	Polyvinyl alcohol	Coating integrity and appearance
Plasticizer	Polyethylene glycol	Coating flexibility
Opacifier and pigment carrier	Titanium dioxide	Color, opacity, light protection
Anti-tacking agent	Talc	Coating process control
Colorants	Iron oxides or other approved pigments, depending on strength	Strength identification and branding

The formulation does not depend on a highly specialized lipid, polymeric, or device-based delivery system. That reduces manufacturing complexity but also lowers the barrier to entry for generic manufacturers.

Which excipient attributes matter most for a generic Rubraca product?

A generic developer should prioritize dissolution reproducibility, tablet robustness, coating performance, and control of rucaparib assay uniformity. The active ingredient is administered at a comparatively high dose, so tablet size, powder flow, compression behavior, and coating weight gain are central development constraints.

Tablet compression and size

The 300 mg strength is the principal design target. A formulation that reproduces the reference product's dissolution while reducing tablet weight can improve swallowing and packaging economics. Excessive compression force may slow disintegration or create capping. Insufficient force can increase friability and chipping during coating and transport.

Microcrystalline cellulose is a logical reference excipient because it supports direct compression and is broadly available from multiple suppliers. Substitution with dibasic calcium phosphate, mannitol, lactose, or co-processed excipients may be possible, but each change affects density, disintegration, moisture sensitivity, and dissolution.

Disintegration and dissolution

Sodium starch glycolate provides a conventional disintegration mechanism. Crospovidone and croscarmellose sodium are potential alternatives, but they are not automatically interchangeable. A generic developer must assess:

• Disintegration time across tablet strengths
• Dissolution under multiple pH conditions
• Sensitivity to compression force
• Impact of lubricant concentration and blending time
• Stability after exposure to humidity
• Relationship between particle-size distribution and dissolution

Because the reference product can be taken with or without food, a substantially different excipient system would require careful evaluation of food-effect risk and comparative bioavailability.[1]

Lubrication and manufacturing scale-up

Magnesium stearate is cost-effective but can cause hydrophobic over-lubrication when blending time or concentration is excessive. Over-lubrication may reduce tablet tensile strength and delay drug release. Alternative lubricants, including sodium stearyl fumarate, may improve robustness in selected processes, but they create a formulation difference that must be supported by dissolution and bioequivalence data.

For a high-volume generic program, the commercial value of a nonmagnesium-stearate formulation would depend on measurable benefits such as improved dissolution control, lower batch failure rates, or better compatibility with continuous manufacturing.

Film coating

The coating is commercially important for color coding, protection against abrasion, and patient identification. Polyvinyl alcohol and polyethylene glycol support a standard aqueous film-coating system. Opportunities include:

• Lower coating weight gain
• Replacement of titanium dioxide where regional regulation or customer preference requires it
• Use of ready-to-use coating systems
• Reduced solvent and energy consumption
• Improved visual differentiation between strengths
• Packaging-compatible coating with lower tablet-to-tablet adhesion

Coating substitutions generally have limited patent value unless tied to a demonstrable stability, dissolution, or manufacturing advantage.

What formulation patents could protect rucaparib products?

The core rucaparib composition and pharmaceutical-use patents are more likely to define the primary exclusion period than the disclosed conventional excipient system. Excipient combinations may be commercially relevant without creating strong standalone patent protection.

A defensible formulation patent would normally require a technically specific feature, such as:

• A defined particle-size distribution for rucaparib camsylate
• A specified salt or crystalline form
• A narrow excipient ratio that improves dissolution or stability
• A low-impurity manufacturing process
• A controlled-release or multiparticulate dosage form
• A formulation that reduces food-effect variability
• A tablet with improved dose loading or reduced tablet mass
• A stability profile under accelerated temperature and humidity conditions

A patent claiming only microcrystalline cellulose, a disintegrant, a lubricant, and a film coat would face a substantial obviousness risk because those ingredients are routine in immediate-release tablets.

The commercially relevant diligence question is whether the live Orange Book-listed patents cover the active ingredient, salt, pharmaceutical composition, method of treatment, or particular formulation. Orange Book review should be performed by product, patent use code, expiration date, pediatric extension, and any listed delisting or withdrawal event.[2]

When does Rubraca lose exclusivity?

Rubraca has a mixed exclusivity profile because different indications received different FDA regulatory outcomes.

Event	Timing and significance
Initial FDA approval	December 2016 for treatment of certain advanced ovarian, fallopian tube, and primary peritoneal cancers after multiple chemotherapy regimens
Maintenance indication	April 2018 approval for recurrent ovarian, fallopian tube, and primary peritoneal cancer responding to platinum-based chemotherapy
Prostate cancer approval	May 2020 under an accelerated approval pathway for selected patients with deleterious BRCA mutation-associated metastatic castration-resistant prostate cancer
Prostate indication	Later subject to withdrawal activity after confirmatory-trial concerns
Advanced ovarian treatment indication	Voluntary withdrawal activity followed unfavorable overall-survival findings from ARIEL4
Continuing commercial core	Recurrent ovarian, fallopian tube, and primary peritoneal cancer maintenance use after response to platinum therapy

Patent expiration is distinct from FDA exclusivity. A generic applicant may pursue a Paragraph IV certification before the latest listed patent expiration, while an ANDA approval may be delayed by a 30-month stay if the patent holder files qualifying litigation within the statutory period.[3]

A precise generic-entry forecast requires a current Orange Book patent table and litigation docket. The practical market assumption is that the maintenance indication remains the most commercially durable label segment, while withdrawn or restricted indications reduce the value of broad method-of-use claims.

What is the Orange Book status of Rubraca?

The Orange Book is the controlling source for listed patents, use codes, pediatric exclusivity, and approved product information.[2] Rubraca's patent risk should be evaluated across four categories:

1. Active-ingredient or chemical-entity claims.
2. Salt, polymorph, or crystalline-form claims.
3. Pharmaceutical-composition or tablet claims.
4. Method-of-use claims covering ovarian or prostate cancer treatment.

Method-of-use patents can create a narrower barrier than composition patents. A generic applicant may seek approval for an indication that avoids a patented use through a section viii statement, subject to labeling and regulatory review. That strategy becomes more difficult when the reference label contains the patented use as the principal commercial indication.

The relevant litigation question is whether a Paragraph IV certification has triggered a patent-infringement action against an ANDA applicant. FDA litigation stays, settlements, covenants not to sue, authorized-generic arrangements, and licensing transactions can materially change the launch date. Patent databases and federal court dockets should be reconciled with the current Orange Book because filed patents and litigated patents are not always identical.

Which companies are challenging Rubraca?

The generic competitive field is likely to include large oral-solid-dose manufacturers with oncology portfolios, regional generic companies, and contract manufacturers seeking ANDA partners. Publicly confirmed challengers should be identified from Paragraph IV notices, district-court complaints, and FDA approval records rather than inferred from product-development rumors.

Potential competitive advantages include:

• Existing rucaparib API supply
• Oncology sales infrastructure
• Ability to finance Paragraph IV litigation
• High-volume tablet capacity
• Established specialty-pharmacy distribution
• Experience with restricted-distribution or REMS-linked oncology products

The first approved generic may capture disproportionate share if it receives 180-day exclusivity or launches under a favorable settlement date. Later entrants typically face rapid price erosion unless the market remains supply constrained.

What generic entry risks exist for Rubraca?

Generic entry risk is moderate to high at the dosage-form level because the product is an immediate-release tablet using conventional excipients. The main barriers are regulatory and patent-related rather than manufacturing-related.

High-risk areas

• Bioequivalence failure caused by dissolution differences
• Inadequate control of rucaparib camsylate particle size
• Patent claims covering the salt or crystalline form
• Use-code restrictions on the maintenance indication
• Delayed API qualification
• Oncology-market reluctance to switch patients
• Commercial uncertainty following indication withdrawals

Lower-risk areas

• Conventional tablet compression
• Standard aqueous film coating
• Multi-source excipient procurement
• Packaging and serialization
• Scale-up from pilot to commercial batches

An ANDA applicant may pursue a formulation that is compositionally different from Rubraca if it demonstrates pharmaceutical equivalence, bioequivalence, and compliance with applicable labeling and patent certifications. A 505(b)(2) strategy would be more relevant to a modified-release, pediatric, liquid, sprinkle, or other differentiated product than to a conventional tablet copy.[3]

What commercial opportunities exist in Rubraca excipients?

The largest opportunity is not a single proprietary excipient. It is a platform supply position across API, excipients, coating systems, and finished-dose manufacturing.

Excipient suppliers

Suppliers can compete through:

• High-purity microcrystalline cellulose
• Low-moisture or engineered disintegrants
• Co-processed direct-compression systems
• Titanium-dioxide-free coating systems
• Ready-to-use film coatings
• Low-peroxide grades for oxidation-sensitive APIs
• Consistent particle-size distributions for scale-up

Supplier qualification is valuable because oncology products require reliable change control, documentation, and continuity of supply. A supplier able to support multiple strengths and multiple manufacturing sites has a stronger commercial position than one offering only a low-cost commodity excipient.

Contract development and manufacturing

CDMOs can offer:

• Rucaparib camsylate formulation development
• Comparative dissolution screening
• Pilot-scale tablet compression
• Film-coating optimization
• Stability programs
• ANDA-ready manufacturing packages
• Commercial production for regional generic launches

The most attractive CDMO proposition is a package that combines formulation development, analytical method transfer, process validation, and regulatory documentation.

Differentiated dosage forms

Potential lifecycle products include:

• Lower-dose tablets for dose titration
• Orally disintegrating tablets
• Sprinkle granules for patients with swallowing difficulty
• Oral suspensions
• Unit-dose blister packs
• Calendar packaging for twice-daily dosing
• Modified-release products designed to reduce peak-related adverse effects

Each option faces clinical, stability, taste-masking, and regulatory hurdles. A pediatric or dysphagia-oriented product would need a defined target population and evidence that the dosage form improves administration without compromising exposure.

How strong is the Rubraca patent estate?

The estate is strongest where claims cover the rucaparib chemical entity, a protected salt or solid form, or a specific therapeutic use supported by the approved label. It is weaker for routine excipient combinations and conventional film-coating systems.

Patent category	Relative strength for generic exclusion	Relevance to excipient strategy
Chemical entity	High if unexpired and valid	May require a noninfringing route or delayed launch
Salt or solid form	Potentially high	Directly affects API sourcing
Specific tablet composition	Medium to high if technically narrow	Can support differentiated formulation
Method of use	Medium, depending on use code and label	May permit carve-out strategies
Conventional excipient mixture	Low to medium	Usually difficult to defend broadly
Manufacturing process	Medium	Can create API or product-supply barriers

Patent strength should be scored against remaining term, claim breadth, prosecution history, prior-art exposure, enforceability, and the commercial importance of the protected indication. A narrow patent can still have high business value if it covers the only approved maintenance use.

What is the FDA regulatory status of Rubraca?

Rubraca remains an FDA-approved rucaparib product, but its indication history has changed. The core regulatory and commercial value is concentrated in ovarian, fallopian tube, and primary peritoneal cancer maintenance treatment following response to platinum-based therapy.[1]

The prostate cancer indication and the use of rucaparib for treatment of heavily pretreated ovarian cancer require separate regulatory analysis because withdrawal or restriction activity reduces the addressable market and may affect method-of-use patent value. FDA labeling, safety communications, approval letters, and the Drugs@FDA database should control current indication analysis.[4]

How does Rubraca compare with competing PARP inhibitors?

Rubraca competes with olaparib, niraparib, and talazoparib. Product selection depends on biomarker status, line of therapy, indication, safety profile, dosing, reimbursement, and patent timing.

Product	Active ingredient	Formulation profile	Commercial implication
Rubraca	Rucaparib camsylate	Immediate-release film-coated tablets	Conventional generic platform; narrower commercial base after indication changes
Lynparza	Olaparib	Tablets and other presentations in selected markets	Larger franchise and broader partnership history
Zejula	Niraparib	Oral capsules/tablets depending market	Competes strongly in ovarian-cancer maintenance
Talzenna	Talazoparib	Oral capsules	Strong prostate and breast cancer positioning

Rubraca's excipient strategy is therefore most attractive for cost-efficient generic entry or a targeted differentiated product, not for a broad platform franchise comparable with the largest PARP inhibitor brands.

Key Takeaways

• Rubraca is an immediate-release rucaparib camsylate film-coated tablet in 200 mg, 250 mg, and 300 mg strengths.
• Its excipient system is conventional and relies on microcrystalline cellulose, sodium starch glycolate, colloidal silicon dioxide, magnesium stearate, and standard film-coating components.
• Generic formulation barriers are manageable; patent, bioequivalence, API quality, and indication-labeling issues are more important.
• Excipient patents are unlikely to provide strong protection unless they claim a narrow, measurable improvement in dissolution, stability, dose loading, or manufacturability.
• The strongest commercial opportunities are generic development, API and excipient supply, oncology-focused CDMO services, and differentiated low-dose or patient-friendly dosage forms.
• Rubraca's commercial value is concentrated in its remaining maintenance indication after withdrawal or restriction of certain historical indications.
• Current Orange Book entries, Paragraph IV notices, court filings, and settlement terms determine the practical generic-entry date.

Frequently Asked Questions

Can a generic Rubraca use different excipients?

Yes. An ANDA applicant can use a different excipient system if the product satisfies pharmaceutical-equivalence, bioequivalence, quality, stability, dissolution, and labeling requirements.

Is rucaparib camsylate difficult to formulate?

It is less formulation-intensive than a poorly soluble controlled-release oncology product, but high-dose tablet loading and dissolution control remain important development issues.

Can an excipient supplier patent a Rubraca substitute formulation?

Potentially, but the claims would need a novel and nonobvious technical feature. A routine substitution of one disintegrant or lubricant for another is unlikely to support broad patent protection.

Would an orally disintegrating Rubraca product have commercial value?

It could address swallowing difficulty and dose administration, but commercial value would depend on taste masking, stability, bioequivalence, manufacturing cost, and freedom to operate.

Does Rubraca have biosimilar risk?

No. Rucaparib is a small-molecule drug. Competitive products would proceed through generic-drug pathways such as an ANDA, not the biosimilar pathway under section 351(k).

References

1. U.S. Food and Drug Administration. (2023). Rubraca (rucaparib) tablets: Prescribing information. FDA.
2. U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations: Orange Book. FDA.
3. U.S. Food and Drug Administration. (2024). Abbreviated new drug application process and patent certifications. FDA.
4. U.S. Food and Drug Administration. (2024). Drugs@FDA: FDA-approved drug products. FDA.