Arguing Significant Benefit Before the COMP When an Authorised EU Treatment Already Exists

Arguing significant benefit before the COMP when an authorised treatment already exists

When a satisfactory method of diagnosis, prevention or treatment is already authorised in the EU for a rare condition, an orphan sponsor must show that its medicine offers significant benefit. That means either a clinically relevant advantage over existing options or a major contribution to patient care (MCPC) ⁶²⁶⁴. The Committee for Orphan Medicinal Products (COMP) tests this twice. The first test is at orphan designation, where an assumption of significant benefit can rest on preliminary data. The second is at marketing authorisation, when the sponsor asks for the designation to be maintained, and there the assumption must be confirmed with the evidence then available ⁶²⁶⁴. The stakes are concrete: the 10-year EU orphan market exclusivity only applies if the criteria, including significant benefit, still hold at approval ⁶².

COMP minutes, orphan maintenance assessment reports and EMA communications show which arguments sponsors use and which ones work. In short, COMP accepts arguments backed by product-specific, comparative data that address every relevant authorised alternative. It rejects arguments that rely on mechanism, convenience or availability alone, on non-inferiority, or on indirect comparisons that cannot handle confounding.

The legal and evidentiary frame

• Two routes. COMP assesses significant benefit either as a clinically relevant advantage (usually efficacy or safety) or as an MCPC. At designation it may accept an assumption supported by preliminary or non-clinical data, but it still expects a data-driven comparison with authorised treatments ⁸¹.
• The comparator set is the authorised products. A sponsor cannot compare against a vague "best standard of care". One melatonin application for burns failed partly because the sponsor did not define best standard of care or show that it covered all EU-authorised products ⁴⁰. COMP also expects the analysis to address specific authorised comparators, for example ramucirumab where it shared the proposed product's mechanism and was authorised for the same line of therapy ¹⁴⁶.
• The bar rises at maintenance. COMP may accept an assumption at designation based on preliminary response data or reasoned practical advantages such as oral rather than IV administration ¹⁴⁵¹⁴⁶. At marketing authorisation a higher level of evidence is required, and holding a designation does not guarantee it will be maintained ¹⁴⁸.
• If no satisfactory method exists, the question falls away. After COMP narrowed a condition to sporadic lymphangioleiomyomatosis, it concluded that no satisfactory authorised treatment existed, so significant benefit did not need to be shown ¹⁴⁹.

Route 1: clinically relevant advantage in efficacy

Direct comparative data: the most reliable argument

Head-to-head evidence against an authorised comparator is the most consistently successful basis:

• Imnovid (pomalidomide). Phase III data showed improved progression-free survival for pomalidomide-bortezomib-dexamethasone versus bortezomib-dexamethasone. COMP accepted significant benefit and recommended that Imnovid not be removed from the Community Register ⁴²⁵⁴.
• Imdylltra (tarlatamab). Pivotal phase 3 data showed improved overall survival (median 13.6 versus 8.3 months) ¹⁶³, progression-free survival and response rate versus standard chemotherapy (mostly topotecan; some patients received lurbinectedin or amrubicin) in extensive-stage small-cell lung cancer, and indirect comparisons supported the advantage versus the CAV regimen ¹¹².
• Voydeya (danicopan). There was no head-to-head trial: the pivotal study added danicopan or placebo to a C5 inhibitor in patients with residual haemolytic anaemia. Comparing across trials, COMP accepted that the combination offers a clinically relevant advantage over Aspaveli, fewer breakthrough-haemolysis events, in patients at risk of severe intravascular haemolysis ¹⁵².
• Tibsovo (ivosidenib). Clinical data showed improved efficacy over azacitidine and decitabine, and indirect comparisons indicated longer overall survival versus venetoclax and glasdegib ⁴⁷.
• Tripotassium citrate / potassium hydrogen carbonate (distal renal tubular acidosis). A crossover non-inferiority study that also showed statistically significantly better efficacy than standard care was accepted as a clinically relevant advantage ⁸⁰.

Non-inferiority alone does not work. For Quinsair (levofloxacin), the sponsor showed non-inferiority to Tobi inhalation solution, but COMP found that non-inferiority itself did not establish significant benefit ⁹⁷.

Indirect comparisons: where the most disputes arise

Where no head-to-head trial exists, sponsors rely on matching-adjusted indirect comparisons (MAIC), simulated treatment comparisons, network meta-analyses or registry matching. The outcome depends on methodological robustness and on the size of the effect.

Accepted:

• Evrysdi (risdiplam). A MAIC supporting improved survival and motor function versus nusinersen in type 1 SMA was accepted. So were broader applicability than onasemnogene abeparvovec, oral administration, and use in patients unsuitable for intrathecal nusinersen. COMP recommended that Evrysdi not be removed ⁵⁶.
• Hetronifly (serplulimab). COMP first recommended removal, finding the matched indirect comparisons with other checkpoint inhibitors unconvincing and exposed to cross-trial bias ¹⁰⁰. On appeal, the sponsor presented anchored MAICs with sensitivity analyses. COMP judged the indirect comparisons robust, citing median overall survival of 15.8 months in the serplulimab trial versus 12.3 and 12.9 months in the atezolizumab and durvalumab trials, and recommended that the designation not be removed ⁵⁹¹¹⁰. The designation no longer stands: Hetronifly was withdrawn from the Community register in April 2026 at the marketing authorisation holder's request, when the terms of the marketing authorisation changed ¹⁶⁴.
• Aspaveli (pegcetacoplan). At the 2021 maintenance review, phase III data versus eculizumab in patients inadequately controlled on eculizumab, plus a MAIC versus ravulizumab, supported maintenance ^123124128. At a later reassessment covering the broader indication, including C5-inhibitor-naïve patients, COMP concluded that the unanchored MAIC did not establish significant benefit ¹²⁵. On appeal the sponsor filed a new MAIC and simulated treatment comparison matched on baseline LDH, real-world switch data, maintenance-of-efficacy data and the mechanistic argument about C3-mediated extravascular haemolysis ⁶⁰. COMP then found that the totality of evidence showed a clinically relevant advantage over Soliris and Ultomiris and recommended the product remain on the register ⁴⁶¹²⁷.

Rejected:

• Empliciti (elotuzumab). Indirect comparisons versus carfilzomib had broad confidence intervals and uncertain subgroups, and overall survival appeared similar or longer with carfilzomib. COMP removed Empliciti from the register by consensus ¹. An efficacy advantage over doxorubicin was accepted, but it could not offset the failure against carfilzomib in the identical indication ⁹⁸.
• Trecondi (treosulfan). In 2019, literature-based indirect comparisons and propensity matching against EBMT registry data were judged vulnerable to confounding, and many pivotal-trial patients could not be matched ⁵. COMP accepted benefit over busulfan and thiotepa but not over melphalan or cyclophosphamide, and recommended removal, so Trecondi was first authorised as a non-orphan medicine ¹⁰⁵. That outcome did not stand. The General Court annulled the removal in Medac v Commission (T-549/19, 23 September 2020), and on 24 November 2020 the Commission authorised Trecondi as an orphan medicine ¹⁶⁵.
• Pyrukynd (mitapivat). A MAIC versus luspatercept was judged exploratory. The populations were not comparable, the effective sample size was much reduced, confounding remained and endpoints differed. It established neither superiority nor the comparability needed to support an MCPC claim ⁴⁵⁵³.
• Pombiliti (cipaglucosidase alfa plus miglustat). The PROPEL pivotal study (ATB200-03) did not robustly show superiority over Myozyme, and uncertainty in the ML-NMR comparison prevented a conclusion versus Nexviadyme ⁴⁸.
• Bylvay (odevixibat), Alagille syndrome. MAIC limitations, bias and dosing differences left efficacy and safety looking similar to Livmarli. The claimed sleep advantage had no comparative Livmarli data behind it, and COMP recommended removal ¹⁰¹.
• Pitolisant (Wakix). An indirect multiple-treatment comparison had unresolved differences in population and setting, and an add-on study missed its primary endpoint ⁷⁹.

The pattern is consistent. Indirect comparisons succeed when effect sizes are large, the analyses are anchored or supported by sensitivity analyses, and they sit alongside direct or real-world evidence. They fail when confounding, unmatched populations or conflicting survival signals are left unresolved.

Targeting a subpopulation underserved by authorised products

Many successful arguments redefine the relevant patients as those that authorised products do not cover.

Accepted:

• Blincyto (blinatumomab). Improved survival in MRD-positive ALL, a population with no authorised treatment ¹⁵¹.
• Reblozyl (luspatercept). Transfusion independence in lower-risk MDS patients who were refractory to, intolerant of or ineligible for ESAs ¹⁵⁸.
• Imbruvica (ibrutinib). Responses in relapsed or refractory Waldenström's macroglobulinaemia, plus a first-line group ineligible for chemoimmunotherapy that had no authorised option ¹³⁹. In CLL, improved progression-free survival in patients with 17p deletion was the main basis for acceptance ⁸⁶.
• Designation-stage examples. Protection from haemolysis in a patient resistant to the authorised PNH treatment ³⁶, and responses in patients who had failed or could no longer receive voriconazole (fosmanogepix, scedosporiosis) ⁸⁴.

Rejected:

• Imnovid (pomalidomide). Arguing benefit for patients excluded from comparator trials (prior allograft, renal or cardiac impairment) did not work. COMP said differences in trial eligibility alone are not enough unless the indication is restricted or the comparator has contraindications that affect a notable share of patients ⁴⁴.
• Jaypirca (pirtobrutinib). The proposed "Tecartus-ineligible" criteria were not in Tecartus's indication or contraindications, there were no consensus CAR-T ineligibility criteria, and post-Tecartus data were inconclusive ¹³⁰¹³³.
• Zynlonta (loncastuximab tesirine). Claims for rapidly progressing patients who could not wait for CAR-T failed because no predefined criteria identified that group and there were no efficacy data for it ¹³⁴. MAICs showed significantly inferior efficacy versus Yescarta and Breyanzi, and COMP recommended removal ¹¹⁶. COMP stated that availability or a new mechanism alone cannot establish significant benefit ⁵⁷⁵⁸.
• Talvey (talquetamab). COMP considered the off-the-shelf advantage over CAR-T clinically relevant, but did not accept significant benefit without demonstrated equivalence to Abecma and Carvykti ⁵¹.

The lesson is that a subpopulation argument needs an objectively definable population, ideally anchored in the comparator's label, together with efficacy data in that population.

Treating disease aspects that authorised products do not reach

COMP has accepted arguments that a product addresses manifestations or mechanisms that the authorised therapy leaves untreated:

• odiparcil for ocular and cartilage involvement in MPS VI ⁹¹
• melatonin for retinitis pigmentosa variants outside Luxturna's scope ⁹⁵
• cysteamine for correcting defective chloride-channel function where authorised cystic fibrosis treatments were symptomatic ⁸⁸
• midostaurin in advanced systemic mastocytosis, where improved survival contrasted with authorised therapies that targeted particular symptoms only ⁸³

A different mechanism without comparative data does not work. COMP rejected that argument where the mechanism could overlap with those of authorised products ¹⁶.

Route 2: clinically relevant advantage in safety

Safety claims succeed when they reflect a real clinical barrier with existing therapy. Afatinib was accepted for head-and-neck cancer in Fanconi anaemia because these patients do not tolerate authorised treatments and there was evidence that afatinib could be tolerated ⁹².

Safety claims fail when they rest on preclinical data or confounded cross-trial comparisons. A second-line acromegaly product was rejected because preclinical diabetes and safety data cannot predict clinical safety ¹⁷. Empliciti's claim of fewer grade 3 or higher adverse events versus carfilzomib was confounded by population differences and had to be weighed against worse survival ⁹⁸.

Route 3: major contribution to patient care

MCPC arguments usually claim a reduced treatment burden at comparable efficacy and safety. COMP accepts them when the burden reduction is shown with product-specific evidence.

Accepted:

Rejected:

• Dosing frequency or convenience alone. Empliciti's two treatments per month versus six IV treatments was rejected because there was no evidence of effects beyond preference, such as quality of life, PROs or adherence ⁹⁸. COMP has also said that moving from three tablets to one daily is not self-evidently significant benefit. Adherence or fewer medication errors must translate into better outcomes ³².
• Palatability or ease of administration without documented problems with existing products. This claim was rejected for the dRTA citrate product even though its efficacy claim succeeded ⁸⁰.
• Modelling instead of data. Less frequent or lower-volume SC dosing predicted only by PK/PD modelling was rejected. COMP wanted data at the intended dose, frequency and volume, including comparative injection-site reaction data ²⁸.
• No product-specific evidence. COMP rejected a needle-free adrenal-crisis product supported only by surveys of existing treatments' shortcomings ³⁴. It also rejected a home SC product where some Member States already allowed home administration of the comparator ²⁶, and an SC anti-FIX inhibitor formulation supported by data from only four patients ¹³.
• MCPC without comparable efficacy. COMP requires comparable efficacy, safety and benefit-risk before it will credit an MCPC. That is why the claims for Talvey, Pyrukynd and Zynlonta failed ^5153116.

What COMP asks for is consistent: validated PROs, quality-of-life data, adherence data or documented complications such as central-line and port events ³⁰³¹. It also scrutinises the reliability of surveys, retrospective analyses and pharmacist follow-up evidence ²⁵.

Designation-stage versus maintenance-stage evidence

At designation, COMP has accepted clinically relevant advantage on non-clinical data alone. Examples include R6/2 mouse-model data in Huntington's disease ⁷⁸, in-vivo sensorimotor recovery for exenatide in traumatic brain injury ⁹⁰ and comparative mercury-chloride models for erdosteine ⁹⁴. It has also accepted improved pharmacokinetics as support for MCPC with efpegsomatropin, although some members dissented because there were no clinical observations with the product ³³.

These assumptions still carry risk. COMP has rejected designation-stage claims resting on uncontrolled case reports ⁸, single-patient data ²², inconclusive non-clinical comparisons ⁹ or no comparative data against the remaining authorised therapies ¹⁰. At maintenance, several designations based on accepted assumptions were not kept: Empliciti and Zynlonta were removed at marketing authorisation, and Bylvay's Alagille syndrome designation was withdrawn in November 2023 ^1116101.

Summary: what succeeded and what failed

Practical implications for sponsors

1. Map every authorised comparator in the defined condition early. COMP evaluates against all of them, and failing against one can sink a COMP maintenance review even when benefit over others is accepted, as Empliciti and COMP's 2019 Trecondi review show ⁹⁸¹⁰⁵.
2. Plan comparative evidence before maintenance. A head-to-head trial is the strongest option. If only indirect evidence is possible, pre-specify anchored methods and sensitivity analyses and add real-world data. The Hetronifly and Aspaveli appeals show that stronger methods can reverse a negative view ¹¹⁰⁶⁰.
3. Define subpopulations using the comparator's label, not trial eligibility. Then generate efficacy data in that group ⁴⁴¹³³.
4. Treat MCPC as an evidence programme. Collect PROs, quality-of-life, adherence and treatment-burden data with the actual product, and show comparable efficacy and safety first ³¹³²⁵¹.
5. Use scientific advice. EMA offers protocol assistance on significant benefit, including parallel advice with CHMP and HTA bodies. COMP handles significant benefit, while HTA bodies look at relative effectiveness ⁶⁶. EMA has also highlighted the value of patient input on contributions to care, quality of life and treatment modality ⁶⁷.