Methods

• CAMMS223 (primary reference)

• Multicentric, phase II, randomised clinical trial

• 49 centres in Europe and the United States

• Randomisation ratio 1:1:1, stratification to balance the study groups with regard to age (< 30 years or ≥ 30 years), gender and baseline EDSS scores (< 2.0 or ≥ 2.0)

• N = 334/available for analysis = 333

• Treatment duration: 24 months

• Follow‐up duration: 36 months

Participants

Inclusion criteria

• Diagnosis of relapsing–remitting MS based on the McDonald criteria

• Onset of symptoms no more than 36 months before the time of screening; at least 2 clinical episodes during the previous 2 years; a score of 3 or less on the EDSS, which ranges from 0 to 10, with higher scores indicating greater disability; and one or more enhancing lesions, as seen on at least one of up to 4 monthly cranial magnetic resonance imaging (MRI) scans.

Exclusion criteria

• Previous disease‐modifying treatments

• History of clinically significant autoimmunity

• Presence of serum antithyrotropin‐receptor antibodies

Interventions

Main interventions 

• Alemtuzumab 12 mg administered IV, once a day for 5 consecutive days at the first month and for 3 consecutive days at months 12 and 24 (the latter at the treating physicians' discretion if the CD4+ T‐cell count was ≥ 100 × 106 cells/L) (n = 113/available for analysis = 112)

• Alemtuzumab 24 mg administered IV, once a day for 5 consecutive days at the first month and for 3 consecutive days at months 12 and 24 (the latter at the treating physicians' discretion if the CD4+ T‐cell count was ≥ 100 × 106 cells/L) (n = 110/available for analysis = 110)

Comparator

• Interferon beta‐1a (44 μg) administered subcutaneously 3 times weekly after dose escalation (n = 111/available for analysis = 111)

All participants received 1 g of intravenous methylprednisolone for 3 days at baseline and at months 12 and 24, coinciding with infusion cycles as premedication for those receiving alemtuzumab. Some participants also received antihistamines or antipyretics at the investigators' discretion

Outcomes

Primary outcome measure

• Rate of participants with sustained accumulation of disability: Disability was assessed according to the ordinal EDSS score. A sustained accumulation of disability was defined as an increase of at least 1.5 points for participants with a baseline score of 0 and of at least 1.0 point for participants with a baseline score of 1.0 or more; all scores were confirmed twice during a 3‐ and 6‐month period. The onset of a sustained level of disability was timed to the first recorded increase in the EDSS score aside from relapse.

• Rate of relapse: Relapse was defined as new or worsening symptoms with an objective change in neurologic examination attributable to multiple sclerosis that lasted for at least 48 hours, that were present at normal body temperature, and that were preceded by at least 30 days of clinical stability.

Secondary outcome measures

• Proportion of participants who did not have a relapse (proportion of participants with relapse‐free survival)

• Changes in lesion burden (as seen on T2‐weighted MRI)

• Brain volume (as measured by the Losseff method on T1‐weighted MRI8)

• Adverse effects, including the following measures:

  • • Thyroid function and levels of antithyrotropin receptor antibodies and lymphocyte subpopulations were measured quarterly at a central laboratory

    • Serum‐binding antibodies against alemtuzumab were measured with the use of a validated enzyme‐linked immunosorbent assay (ELISA) at BioAnaLab

    • Immune thrombocytopenia by single confirmed platelet count of fewer than 50,000 per microlitre without clumping or a platelet count of more than 50,000 but fewer than 100,000 per microlitre on at least 2 consecutive occasions during a period of at least 1 month, with normal haemoglobin, neutrophil and eosinophil counts; an absence of splenomegaly; and a normal peripheral‐blood smear (apart from thrombocytopenia).

All adverse events with an onset up to 36 months were reported. In addition, all serious adverse events and autoimmune‐associated disorders occurring before 1 March 2008, were listed. A subsequent adverse event of Burkitt's lymphoma not associated with Epstein–Barr virus (EBV) was also included in this report.

Notes

• The effectiveness of blinding was assessed at the end‐of‐study visit.

• Participants with an increased level of disability could be discontinued from the study.

• There was no active monitoring for progressive multifocal leukoencephalopathy.

• Preplanned interim analyses were performed when most participants had completed at least 1 year and 2 years with a prespecified alpha spending function. Disclosure of these results formed part of safety announcements by the sponsor in September 2005 and 2006. After the interim analyses, P values of less than 0.016 and 0.004 were considered to have statistical significance for the rates of sustained disability and relapse, respectively.

• In September 2005, the data and safety monitoring board recommended suspension of alemtuzumab treatments after receiving reports of 3 cases of immune thrombocytopenic purpura, including 1 death. All safety and efficacy assessments proceeded as planned and participants who were receiving interferon beta‐1a continued to receive the drug. At the time of dose suspension, only 2 eligible participants (1%) had not received the second cycle of alemtuzumab at month 12, whereas 155 participants (75%) were precluded from receiving the third cycle of alemtuzumab at month 24.

• More participants discontinued interferon beta‐1a than alemtuzumab, principally because of a lack of efficacy and adverse events, so that only 59% of the original group of participants receiving interferon beta‐1a completed the 36‐month study, as compared with 83% of participants receiving alemtuzumab. At the end of the study review, 90% and 91% of raters remained unaware of assignments to the group receiving interferon beta‐1a and the group receiving alemtuzumab, respectively.

• Funding: Genzyme

Risk of bias

Bias

Authors' judgement

Support for judgement

Random sequence generation (selection bias)

Low risk

Eligible participants were randomly assigned in a 1:1:1 with the use of the Pocock and Simon minimisation algorithm.

Allocation concealment (selection bias)

Unclear risk

No information available to allow a judgement

Blinding of participants and personnel (performance bias)
All outcomes

High risk

Both study drugs have adverse effects that precluded masking of participants and treating clinicians to treatment assignment

Blinding of outcome EDSS assessment
EDSS

Low risk

"EDSS scores were determined quarterly in a blinded fashion by a neurologist who also adjudicated possible relapses".

Blinding of outcome assessment (detection bias)
All outcomes, except EDSS

Low risk

"MRI scans were performed annually and interpreted by a neuroradiologist who was unaware of assignments to study groups".

Blinding of safety outcome assessment

High risk

"Safety was assessed quarterly by the treating neurologist, who was aware of study‐group assignment".

Incomplete outcome data (attrition bias)
All outcomes

Low risk

Number and reasons of withdrawals were similar in the interventions and control arms.

Selective reporting (reporting bias)

Low risk

—

Other bias

Low risk

—

Methods

• CARE‐MS I (primary reference)

• Multicentric, phase III, randomised clinical trial

• 101 academic medical centres and clinical practices in 16 countries

• Randomisation ratio 2:1; stratification by site

• N = 581/available for analysis = 563

• Treatment duration: 12 months

• Follow‐up duration: 24 months

Participants

Inclusion criteria

• 18 to 50 years of age

• Diagnosis of relapsing‐remitting multiple sclerosis fulfilling the McDonald criteria

• Disease duration of up to 5 years

• At least 2 relapses in the previous 2 years and at least 1 in the previous year

• Expanded disability status scale (EDSS) 10 scores of 3.0 or lower

• Cranial abnormalities on MRI attributable to multiple sclerosis

Exclusion criteria

• Progressive disease course

• Previous multiple sclerosis disease therapy (apart from corticosteroids)

• Previous immunosuppressive, investigational or monoclonal antibody therapy

• Clinically significant autoimmunity other than multiple sclerosis

Interventions

Main interventions 

• Alemtuzumab 12 mg administered IV, once a day for 5 consecutive days at baseline and for 3 consecutive days at 12 months (n = 386/available for analysis = 376)

After a protocol amendment in January 2009, alemtuzumab participants received oral aciclovir 200 mg twice daily during alemtuzumab infusion and for 28 days thereafter as prophylaxis against herpes infection.

Comparator

• Interferon beta‐1a 44 μg given subcutaneously 3 times weekly after dose titration (n = 195/available for analysis = 187)

Participants in both groups received 1 g per day of intravenous methylprednisolone on 3 consecutive days at baseline and at month 12. Concomitant treatment with an antipyretic or antihistamine drug was allowed, at the discretion of the treating neurologist.

Outcomes

Primary outcome measures

• Relapse rate, defined as new or worsening neurological symptoms attributable to MS, lasting at least 48 hours, without pyrexia, after at least 30 days of clinical stability, with an objective change on neurological examination assessed by a masked rater. The relapse adjudication panel decided the status of suspected relapses on the basis of the protocol definition and their masked review of all data collected by the site, including whether there was an objective change corresponding to current relapse symptoms (1 point on 2 functional system scales or 2 points on 1 functional system scale or increase in the EDSS score).

• Sustained accumulation of disability, defined as an increase from baseline of at least 1 EDSS point (or ≥1.5 points if baseline EDSS score was 0) confirmed over 6 months.

Secondary outcome measure (24 months)

• Rate of relapse‐free participants

• Change in EDSS

• Number of participants with new or enlarging T2‐hyperintense lesions on magnetic resonance imaging

• Change in multiple sclerosis functional composite (MSFC)

• Freedom from clinical disease activity, defined as absence both of relapses and sustained accumulation of disability

• Freedom from MRI disease activity, defined as absence both of gadolinium‐enhancing lesions and new or enlarging T2‐hyperintense lesions

• Adverse events, actively searched by a monthly questionnaire follow‐up of participants, complete blood counts, serum creatinine, urinalysis and microscopy monthly (every 3 months for participants in the interferon beta‐1a group), and thyroid function tests every 3 months

Notes

• Raters completed a questionnaire assessing quality of the masking at each EDSS assessment

• All participants who received at least one dose of study drug were included in the efficacy and safety analyses according to treatment assignment ("modified ITT analysis")

• Funding: Genzyme. The study sponsor was involved in the design and undertaking of the trial, data analysis and interpretation, writing of the manuscript, and the decision to submit the manuscript for publication. Bayer Schering Pharma participated in the design and oversight of the trial. Clinical investigators collaborated with the sponsor to design and oversee the trial. The sponsor did the statistical analyses.

Risk of bias

Bias

Authors' judgement

Support for judgement

Random sequence generation (selection bias)

Low risk

"We randomly allocated patients using an interactive voice response system"

Allocation concealment (selection bias)

Low risk

Use of an interactive voice response system

Blinding of participants and personnel (performance bias)
All outcomes

High risk

"Both study drugs have adverse effects that precluded masking of patients and treating clinicians to treatment assignment, and subcutaneous interferon beta 1a was available only in proprietary prefilled syringes that could not effectively be duplicated for placebo"

Blinding of outcome EDSS assessment
EDSS

High risk

"In the absence of a masked rater, unmasked raters could submit EDSS assessments"

Blinding of outcome assessment (detection bias)
All outcomes, except EDSS

Low risk

"Stringent clinical and MRI rater masking, and adjudication of relapses by a committee comprising six independent and masked neurologists"

Blinding of safety outcome assessment

Low risk

"Stringent clinical and MRI rater masking, and adjudication of relapses by a committee comprising six independent and masked neurologists"

Incomplete outcome data (attrition bias)
All outcomes

High risk

Only participants who received at least one dose of study drugs were included in the efficacy and safety analyses according to treatment assignment (modified ITT analysis)

Selective reporting (reporting bias)

Low risk

—

Other bias

Low risk

Methods

• CARE‐MS II (primary reference)

• Multicentric, phase III, randomised clinical trial

• 194 centres around the world

• N = 798/available for analysis = 667

• Randomisation ratio 1:2:2

• Treatment duration: 12 months

• Follow‐up: 24 months

Participants

Inclusion criteria:

• 18 to 55 years of age

• Diagnosis of relapsing‐remitting MS fulfilling the McDonald diagnostic criteria

• Disease duration of 10 years or less

• At least 2 relapses in the previous 2 years, with at least 1 in the previous year

• At least 1 relapse while on interferon beta or glatiramer acetate after at least 6 months of treatment

• Expanded Disability Status Scale (EDSS) scores of 5.0 or less

• Cranial and spinal MRI lesions fulfilling protocol‐defined criteria (MRI scan demonstrating white matter lesions attributable to MS)

Exclusion criteria:

• Previous treatment with alemtuzumab

• Previous treatment with any investigational drug (i.e. a medication that is not approved at any dose or for any indication)

• Treatment with natalizumab, methotrexate, azathioprine or cyclosporine in the past 6 months

• Previous treatment with mitoxantrone, cyclophosphamide, cladribine, rituximab or any other immunosuppressive, or cytotoxic therapy (other than steroid treatment)

• Any progressive form of MS

• Any disability acquired from trauma or another illness that could interfere with evaluation of disability due to MS

• Major systemic disease that cannot be treated or adequately controlled by therapy

• Active infection or high risk of infection

• Autoimmune disorder (other than MS)

• Impaired hepatic or renal function

• History of malignancy, except basal skin cell carcinoma

• Medical, psychiatric, cognitive or other conditions that compromise the patient's ability to understand the patient information, to give informed consent, to comply with the trial protocol or to complete the study

• Known bleeding disorder

• Women of childbearing potential with a positive serum pregnancy test, pregnant or lactating

• Current participation in another clinical study or previous participation in CAMMS323 (NCT00530348)

• Previous hypersensitivity reaction to any immunoglobulin product

• Known allergy or intolerance to interferon beta, human albumin or mannitol

• Intolerance of pulsed corticosteroids, especially a history of steroid psychosis

• Inability to self administer subcutaneous (SC) injections or receive SC injections from caregiver

• Inability to undergo MRI with gadolinium administration

• Unwilling to use a reliable and acceptable contraceptive method throughout the study period (fertile participants only)

Interventions

Main Interventions 

• Alemtuzumab 12 mg per day administered IV, once a day for 5 consecutive days at Month 0 and 12 mg per day administered through IV, once a day for 3 consecutive days at Month 12 (n = 436, available for analysis = 426)

• Alemtuzumab  24 mg per day administered IV, once a day for 5 consecutive days at Month 0 and 24 mg per day administered IV, once a day for 3 consecutive days at Month 12 (n = 173, available for analysis = 170)

 Alemtuzumab was administered in 2 annual cycles, once at the beginning of the study and again 1 year later

Comparator

• Interferon beta‐1a (Rebif®) 44 µg administered 3 times weekly by subcutaneous self injections (n = 231, available for analysis = 202)

Outcomes

 Primary outcome measure 

• Time to Sustained Accumulation of Disability (SAD) (time frame: 2 years)

• Relapse rate (time frame: 2 years). Relapse was defined as new or worsening symptoms with an objective changes in neurologic examination attributable to multiple sclerosis that lasted for at least 48 hours, that were present at normal body temperature and that were preceded by at least 30 days of clinical stability.

Secondary outcome measures

• Rate of participants who are relapse‐free at year 2 (time frame: 2 years)

• Change from baseline in EDSS (Expanded Disability Status Scale) (time frame: 2 years)

• Acquisition of disability as measured by change from baseline in Multiple Sclerosis Functional Composite (MSFC) (time frame: 2 years)

• Number of participants with new or enlarging T2‐hyperintense lesions in magnetic resonance

• Adverse effects

• Quality of life: assessed by Functional Assessment of Multiple Sclerosis (FAMS; scale 0 to 176 for total score); Medical Outcomes Study 36‐Item Short‐Form Survey (SF‐36; scale 1 to 100; healthy population mean = 50; administered annually in the core study); and EuroQol in 5 Dimensions visual analogue scale (EQ‐5D VAS; scale 0 to 100).

Co‐primary endpoints were relapse rate and time to 6‐month sustained accumulation of disability, comparing alemtuzumab 12 mg and interferon beta‐1a in all participants who received at least one dose of study drug.

Notes

• The 24 mg per day group was discontinued to aid recruitment, but data were included for safety assessments. The decision to close recruitment into the alemtuzumab 24 mg arm was made by the Neurology Steering Committee and Genzyme management without review of safety or efficacy data from this study.

• Raters completed a questionnaire assessing quality of the masking at each EDSS assessment.

• Funding: Genzyme (Sanofi) and Bayer ‐ Schering Pharma.

Risk of bias

Bias

Authors' judgement

Support for judgement

Random sequence generation (selection bias)

Low risk

"We randomly allocated patients with an interactive voice response system in a 2:2:1 scheme"

Allocation concealment (selection bias)

Low risk

Use of an interactive voice response system

Blinding of participants and personnel (performance bias)
All outcomes

High risk

"Because both study drugs had adverse effects that precluded double‐blinding, and interferon beta 1a proprietary syringes could not effectively be duplicated for placebo"

Blinding of outcome EDSS assessment
EDSS

High risk

"In the absence of a masked rater, unmasked raters could submit EDSS assessments"

Blinding of outcome assessment (detection bias)
All outcomes, except EDSS

Low risk

"Raters were masked to treatment‐group assignment"

Blinding of safety outcome assessment

Low risk

"Raters were masked to treatment‐group assignment"

Incomplete outcome data (attrition bias)
All outcomes

Unclear risk

—

Selective reporting (reporting bias)

High risk

Efficacy outcomes for alemtuzumab 24 mg were not provided.

The results from some previously planned outcomes were not provided (i.e. quality of life)

Other bias

Low risk