Adjunctive brivaracetam and sustained seizure frequency reduction in very active focal epilepsy.

OBJECTIVE: This study aimed to explore the effectiveness of brivaracetam (BRV) according to baseline seizure frequency and past treatment history in subjects with focal epilepsy who were included in the Brivaracetam Add-On First Italian Network Study (BRIVAFIRST). METHODS: BRIVAFIRST was a 12-month retrospective, multicenter study including adults prescribed adjunctive BRV. Study outcomes included sustained seizure response (SSR), sustained seizure freedom (SSF), and the rates of treatment discontinuation and adverse events (AEs). Baseline seizure frequency was stratified as <5, 5-20, and >20 seizures per month, and the number of prior antiseizure medications (ASMs) as <5 and ≥6. RESULTS: A total of 994 participants were included. During the 1-year study period, SSR was reached by 45.8%, 39.3%, and 22.6% of subjects with a baseline frequency of <5, 5-20, and >20 seizures per month (p < .001); the corresponding figures for the SSF were 23.4%, 9.8%, and 2.8% (p < .001). SSR was reached by 51.2% and 26.5% participants with a history of 1-5 and ≥6 ASMs (p < .001); the corresponding rates of SSF were 24.7% and 4.5% (p < .001). Treatment discontinuation due to lack of efficacy was more common in participants with >20 seizures compared to those with <5 seizures per month (25.8% vs. 9.3%, p < .001), and in participants with history of ≥6 prior ASMs compared to those with history of 1-5 ASMs (19.6% vs. 12.2%, p = .002). There were no differences in the rates of BRV withdrawal due to AEs and the rates of AEs across the groups of participants defined according to the number of seizures at baseline and the number of prior ASMs. SIGNIFICANCE: The baseline seizure frequency and the number of previous ASMs were predictors of sustained seizure frequency reduction with adjunctive BRV in subjects with focal epilepsy.

Brivaracetam as Early Add-On Treatment in Patients with Focal Seizures: A Retrospective, Multicenter, Real-World Study.

INTRODUCTION: In randomized controlled trials, add-on brivaracetam (BRV) reduced seizure frequency in patients with drug-resistant focal epilepsy. Most real-world research on BRV has focused on refractory epilepsy. The aim of this analysis was to assess the 12-month effectiveness and tolerability of adjunctive BRV when used as early or late adjunctive treatment in patients included in the BRIVAracetam add-on First Italian netwoRk Study (BRIVAFIRST). METHODS: BRIVAFIRST was a 12-month retrospective, multicenter study including adult patients prescribed adjunctive BRV. Effectiveness outcomes included the rates of sustained seizure response, sustained seizure freedom, and treatment discontinuation. Safety and tolerability outcomes included the rate of treatment discontinuation due to adverse events (AEs) and the incidence of AEs. Data were compared for patients treated with add-on BRV after 1-2 (early add-on) and ≥ 3 (late add-on) prior antiseizure medications. RESULTS: A total of 1029 patients with focal epilepsy were included in the study, of whom 176 (17.1%) received BRV as early add-on treatment. The median daily dose of BRV at 12 months was 125 (100-200) mg in the early add-on group and 200 (100-200) in the late add-on group (p < 0.001). Sustained seizure response was reached by 97/161 (60.3%) of patients in the early add-on group and 286/833 (34.3%) of patients in the late add-on group (p < 0.001). Sustained seizure freedom was achieved by 51/161 (31.7%) of patients in the early add-on group and 91/833 (10.9%) of patients in the late add-on group (p < 0.001). During the 1-year study period, 29 (16.5%) patients in the early add-on group and 241 (28.3%) in the late add-on group discontinued BRV (p = 0.001). Adverse events were reported by 38.7% and 28.5% (p = 0.017) of patients who received BRV as early and late add-on treatment, respectively. CONCLUSION: Brivaracetam was effective and well tolerated both as first add-on and late adjunctive treatment in patients with focal epilepsy.

Sustained seizure freedom with adjunctive brivaracetam in patients with focal onset seizures.

The maintenance of seizure control over time is a clinical priority in patients with epilepsy. The aim of this study was to assess the sustained seizure frequency reduction with adjunctive brivaracetam (BRV) in real-world practice. Patients with focal epilepsy prescribed add-on BRV were identified. Study outcomes included sustained seizure freedom and sustained seizure response, defined as a 100% and a ≥50% reduction in baseline seizure frequency that continued without interruption and without BRV withdrawal through the 12-month follow-up. Nine hundred ninety-four patients with a median age of 45 (interquartile range = 32-56) years were included. During the 1-year study period, sustained seizure freedom was achieved by 142 (14.3%) patients, of whom 72 (50.7%) were seizure-free from Day 1 of BRV treatment. Sustained seizure freedom was maintained for ≥6, ≥9, and 12 months by 14.3%, 11.9%, and 7.2% of patients from the study cohort. Sustained seizure response was reached by 383 (38.5%) patients; 236 of 383 (61.6%) achieved sustained ≥50% reduction in seizure frequency by Day 1, 94 of 383 (24.5%) by Month 4, and 53 of 383 (13.8%) by Month 7 up to Month 12. Adjunctive BRV was associated with sustained seizure frequency reduction from the first day of treatment in a subset of patients with uncontrolled focal epilepsy.

Adjunctive Brivaracetam in Older Patients with Focal Seizures: Evidence from the BRIVAracetam add­on First Italian netwoRk Study (BRIVAFIRST).

BACKGROUND: The management of epilepsy in older adults has become part of daily practice because of an aging population. Older patients with epilepsy represent a distinct and more vulnerable clinical group as compared with younger patients, and they are generally under-represented in randomized placebo-controlled trials. Real-world studies can therefore be a useful complement to characterize the drug's profile. Brivaracetam is a rationally developed compound characterized by high-affinity binding to synaptic vesicle protein 2A and approved as adjunctive therapy for focal seizures in adults with epilepsy. OBJECTIVE: The aim of this study was to assess the 12-month effectiveness and tolerability of adjunctive brivaracetam in older patients (≥65 years of age) with epilepsy treated in a real-world setting. METHODS: The BRIVAFIRST (BRIVAracetam add-on First Italian netwoRk STudy) was a 12-month retrospective multicenter study including adult patients prescribed adjunctive brivaracetam. Effectiveness outcomes included the rates of seizure response (≥50% reduction in baseline seizure frequency), seizure freedom, and treatment discontinuation. Safety and tolerability outcomes included the rate of treatment discontinuation due to adverse events and the incidence of adverse events. Data were compared for patients aged ≥65 years of age ('older') vs those aged <65 years ('younger'). RESULTS: There were 1029 patients with focal epilepsy included in the study, of whom 111 (10.8%) were aged ≥65 years. The median daily dose of brivaracetam at 3 months was 100 [interquartile range, 100-175] mg in the older group and 100 [100-200] mg in the younger group (p = 0.036); it was 150 [100-200] mg in both groups either at 6 months (p = 0.095) or 12 months (p = 0.140). At 12 months, 49 (44.1%) older and 334 (36.4%) younger patients had a reduction in their baseline seizure frequency by at least 50% (p = 0.110), and the seizure freedom rates were 35/111 (31.5%) and 134/918 (14.6%) in older and younger groups, respectively (p < 0.001). During the 1-year study period, 20 (18.0%) patients in the older group and 245 (26.7%) patients in the younger group discontinued brivaracetam (p = 0.048). Treatment withdrawal because of insufficient efficacy was less common in older than younger patients [older: n = 7 (6.3%), younger: n = 152 (16.6%); p = 0.005]. Adverse events were reported by 24.2% of older patients and 30.8% of younger patients (p = 0.185); the most common adverse events were somnolence, nervousness and/or agitation, vertigo, and fatigue in both study groups. CONCLUSIONS: Adjunctive brivaracetam was efficacious, had good tolerability, and no new or unexpected safety signals emerged when used to treat older patients with uncontrolled focal seizures in clinical practice. Adjunctive brivaracetam can be a suitable therapeutic option in this special population.

Brivaracetam as add-on treatment in patients with post-stroke epilepsy: real-world data from the BRIVAracetam add-on First Italian netwoRk Study (BRIVAFIRST).

OBJECTIVE: Post-stroke epilepsy (PSE) is one of the most common causes of acquired epilepsy and accounts for about 10-15% of all newly diagnosed epilepsy cases. However, evidence about the clinical profile of antiseizure medications in the PSE setting is currently limited. Brivaracetam (BRV) is a rationally developed compound characterized by high-affinity binding to synaptic vesicle protein 2A. The aim of this study was to assess the 12-month effectiveness and tolerability of adjunctive BRV in patients with PSE treated in a real-world setting. METHODS: This was a subgroup analysis of patients with PSE included in the BRIVAracetam add-on First Italian netwoRk Study (BRIVAFIRST). The BRIVAFIRST was a 12-month retrospective, multicentre study including adult patients prescribed adjunctive BRV. Effectiveness outcomes included the rates of seizure response (≥50% reduction in baseline seizure frequency), seizure-freedom, and treatment discontinuation. Safety and tolerability outcomes included the rate of treatment discontinuation due to adverse events (AEs) and the incidence of AEs. RESULTS: Patients with PSE included in the BRIVAFIRST were 75 and had a median age of 57 (interquartile range, 42-66) years. The median daily doses of BRV at 3, 6, and 12 months from starting treatment were 100 (100-150) mg, 125 (100-200) mg and 100 (100-200) mg, respectively. At 12 months, 32 (42.7%) patients had a reduction in their baseline seizure frequency by at least 50%, and the seizure freedom rates was 26/75 (34.7%). During the 1-year study period, 10 (13.3%) patients discontinued BRV. The reasons of treatment withdrawal were insufficient efficacy in 6 (8.0%) patients and poor tolerability in 4 (5.3%) patients. Adverse events were reported by 13 (20.3%) patients and were rated as mild in 84.6% and moderate in 15.4% of cases. SIGNIFICANCE: Adjunctive BRV was efficacious and generally well-tolerated when used in patients with PSE in clinical practice. Adjunctive BRV can be a suitable therapeutic option for patients with PSE.

Early reversible leukoencephalopathy and unilateral sixth cranial nerve palsy in mild COVID-19 infection.

OBJECTIVES: To provide new insights into neurological manifestations of COVID-19. We describe a patient with mild COVID-19 associated with diplopia from right sixth cranial nerve palsy and early diffuse leukoencephalopathy, successfully treated with intravenous methylprednisolone. METHODS: The patient was evaluated for diplopia that occurred 1 day after the onset of fever, myalgia, and headache. A complete neurological workup, including neurological examination, cerebrospinal fluid (CSF) analysis with viral polymerase chain reaction (PCR), serum autoimmune encephalitis, and anti-nerve antibodies and brain magnetic resonance imaging (MRI), was performed. RESULTS: Clinical examination revealed incomplete right sixth cranial nerve palsy. Brain MRI showed diffuse confluent fluid-attenuated inversion recovery (FLAIR) hyperintense white matter abnormalities, while CSF analysis showed mild hyperproteinorrachia (61 mg/dL) without pleocytosis. The patients were treated with high-dose intravenous methylprednisolone with rapid improvement of neurological symptoms and resolution of CSF and MRI abnormalities. DISCUSSION: Our report shows that COVID-19 may predominantly present with neurological symptoms; furthermore, it argues the notion of leukoencephalopathy as a typical feature of a severe case of the disease. Mechanisms underpinning neurological symptoms in COVID-19 still need to be elucidated; nonetheless, early recognition and prompt management may ensure their improvement or even complete recovery and are therefore recommended.

Adjunctive Brivaracetam in Focal Epilepsy: Real-World Evidence from the BRIVAracetam add-on First Italian netwoRk STudy (BRIVAFIRST).

BACKGROUND: In randomized controlled trials, add-on brivaracetam (BRV) reduced seizure frequency in patients with drug-resistant focal epilepsy. Studies performed in a naturalistic setting are a useful complement to characterize the drug profile. OBJECTIVE: This multicentre study assessed the effectiveness and tolerability of adjunctive BRV in a large population of patients with focal epilepsy in the context of real-world clinical practice. METHODS: The BRIVAFIRST (BRIVAracetam add-on First Italian netwoRk STudy) was a retrospective, multicentre study including adult patients prescribed adjunctive BRV. Patients with focal epilepsy and 12-month follow-up were considered. Main outcomes included the rates of seizure-freedom, seizure response (≥ 50% reduction in baseline seizure frequency), and treatment discontinuation. The incidence of adverse events (AEs) was also considered. Analyses by levetiracetam (LEV) status and concomitant use of strong enzyme-inducing antiseizure medications (EiASMs) and sodium channel blockers (SCBs) were performed. RESULTS: A total of 1029 patients with a median age of 45 years (33-56) was included. At 12 months, 169 (16.4%) patients were seizure-free and 383 (37.2%) were seizure responders. The rate of seizure freedom was 22.3% in LEV-naive patients, 7.1% in patients with prior LEV use and discontinuation due to insufficient efficacy, and 31.2% in patients with prior LEV use and discontinuation due to AEs (p < 0.001); the corresponding values for ≥ 50% seizure frequency reduction were 47.9%, 29.7%, and 42.8% (p < 0.001). There were no statistically significant differences in seizure freedom and seizure response rates by use of strong EiASMs. The rates of seizure freedom (20.0% vs. 16.6%;  p = 0.341) and seizure response (39.7% vs. 26.9%; p = 0.006) were higher in patients receiving SCBs than those not receiving SCBs; 265 (25.8%) patients discontinued BRV. AEs were reported by 30.1% of patients, and were less common in patients treated with BRV and concomitant SCBs than those not treated with SCBs (28.9% vs. 39.8%; p = 0.017). CONCLUSION: The BRIVAFIRST provided real-world evidence on the effectiveness of BRV in patients with focal epilepsy irrespective of LEV history and concomitant ASMs, and suggested favourable therapeutic combinations.

Treatment with disease-modifying drugs for people with a first clinical attack suggestive of multiple sclerosis.

BACKGROUND: The treatment of multiple sclerosis has changed over the last 20 years. The advent of disease-modifying drugs in the mid-1990s heralded a period of rapid progress in the understanding and management of multiple sclerosis. With the support of magnetic resonance imaging early diagnosis is possible, enabling treatment initiation at the time of the first clinical attack. As most of the disease-modifying drugs are associated with adverse events, patients and clinicians need to weigh the benefit and safety of the various early treatment options before taking informed decisions. OBJECTIVES: 1. to estimate the benefit and safety of disease-modifying drugs that have been evaluated in all studies (randomised or non-randomised) for the treatment of a first clinical attack suggestive of MS compared either with placebo or no treatment;2. to assess the relative efficacy and safety of disease-modifying drugs according to their benefit and safety;3. to estimate the benefit and safety of disease-modifying drugs that have been evaluated in all studies (randomised or non-randomised) for treatment started after a first attack ('early treatment') compared with treatment started after a second attack or at another later time point ('delayed treatment'). SEARCH METHODS: We searched the Cochrane Multiple Sclerosis and Rare Diseases of the CNS Group Trials Register, MEDLINE, Embase, CINAHL, LILACS, clinicaltrials.gov, the WHO trials registry, and US Food and Drug Administration (FDA) reports, and searched for unpublished studies (until December 2016). SELECTION CRITERIA: We included randomised and observational studies that evaluated one or more drugs as monotherapy in adult participants with a first clinical attack suggestive of MS. We considered evidence on alemtuzumab, azathioprine, cladribine, daclizumab, dimethyl fumarate, fingolimod, glatiramer acetate, immunoglobulins, interferon beta-1b, interferon beta-1a (Rebif®, Avonex®), laquinimod, mitoxantrone, natalizumab, ocrelizumab, pegylated interferon beta-1a, rituximab and teriflunomide. DATA COLLECTION AND ANALYSIS: Two teams of three authors each independently selected studies and extracted data. The primary outcomes were disability-worsening, relapses, occurrence of at least one serious adverse event (AE) and withdrawing from the study or discontinuing the drug because of AEs. Time to conversion to clinically definite MS (CDMS) defined by Poser diagnostic criteria, and probability to discontinue the treatment or dropout for any reason were recorded as secondary outcomes. We synthesized study data using random-effects meta-analyses and performed indirect comparisons between drugs. We calculated odds ratios (OR) and hazard ratios (HR) along with relative 95% confidence intervals (CI) for all outcomes. We estimated the absolute effects only for primary outcomes. We evaluated the credibility of the evidence using the GRADE system. MAIN RESULTS: We included 10 randomised trials, eight open-label extension studies (OLEs) and four cohort studies published between 2010 and 2016. The overall risk of bias was high and the reporting of AEs was scarce. The quality of the evidence associated with the results ranges from low to very low. Early treatment versus placebo during the first 24 months' follow-upThere was a small, non-significant advantage of early treatment compared with placebo in disability-worsening (6.4% fewer (13.9 fewer to 3 more) participants with disability-worsening with interferon beta-1a (Rebif®) or teriflunomide) and in relapses (10% fewer (20.3 fewer to 2.8 more) participants with relapses with teriflunomide). Early treatment was associated with 1.6% fewer participants with at least one serious AE (3 fewer to 0.2 more). Participants on early treatment were on average 4.6% times (0.3 fewer to 15.4 more) more likely to withdraw from the study due to AEs. This result was mostly driven by studies on interferon beta 1-b, glatiramer acetate and cladribine that were associated with significantly more withdrawals for AEs. Early treatment decreased the hazard of conversion to CDMS (HR 0.53, 95% CI 0.47 to 0.60). Comparing active interventions during the first 24 months' follow-upIndirect comparison of interferon beta-1a (Rebif®) with teriflunomide did not show any difference on reducing disability-worsening (OR 0.84, 95% CI 0.43 to 1.66). We found no differences between the included drugs with respect to the hazard of conversion to CDMS. Interferon beta-1a (Rebif®) and teriflunomide were associated with fewer dropouts because of AEs compared with interferon beta-1b, cladribine and glatiramer acetate (ORs range between 0.03 and 0.29, with substantial uncertainty). Early versus delayed treatmentWe did not find evidence of differences between early and delayed treatments for disability-worsening at a maximum of five years' follow-up (3% fewer participants with early treatment (15 fewer to 11.1 more)). There was important variability across interventions; early treatment with interferon beta-1b considerably reduced the odds of participants with disability-worsening during three and five years' follow-up (OR 0.52, 95% CI 0.32 to 0.84 and OR 0.57, 95% CI 0.36 to 0.89). The early treatment group had 19.6% fewer participants with relapses (26.7 fewer to 12.7 fewer) compared to late treatment at a maximum of five years' follow-up and early treatment decreased the hazard of conversion to CDMS at any follow-up up to 10 years (i.e. over five years' follow-up HR 0.62, 95% CI 0.53 to 0.73). We did not draw any conclusions on long-term serious AEs or discontinuation due to AEs because of inadequacies in the available data both in the included OLEs and cohort studies. AUTHORS' CONCLUSIONS: Very low-quality evidence suggests a small and uncertain benefit with early treatment compared with placebo in reducing disability-worsening and relapses. The advantage of early treatment compared with delayed on disability-worsening was heterogeneous depending on the actual drug used and based on very low-quality evidence. Low-quality evidence suggests that the chances of relapse are less with early treatment compared with delayed. Early treatment reduced the hazard of conversion to CDMS compared either with placebo, no treatment or delayed treatment, both in short- and long-term follow-up. Low-quality evidence suggests that early treatment is associated with fewer participants with at least one serious AE compared with placebo. Very low-quality evidence suggests that, compared with placebo, early treatment leads to more withdrawals or treatment discontinuation due to AEs. Difference between drugs on short-term benefit and safety was uncertain because few studies and only indirect comparisons were available. Long-term safety of early treatment is uncertain because of inadequately reported or unavailable data.

Evading the Vainshtein Mechanism with Anomalous Gravitational Wave Speed: Constraints on Modified Gravity from Binary Pulsars.

By using observations of the Hulse-Taylor pulsar, we constrain the gravitational wave (GW) speed to the level of 10(-2). We apply this result to scalar-tensor theories that generalize Galileon 4 and 5 models, which display anomalous propagation speed and coupling to matter for GWs. We argue that this effect survives conventional screening due to the persistence of a scalar field gradient inside virialized overdensities, which effectively "pierces" the Vainshtein screening. In specific branches of solutions, our result allows us to directly constrain the cosmological couplings in the effective field theory of dark energy formalism.

New class of consistent scalar-tensor theories.

We introduce a new class of scalar-tensor theories of gravity that extend Horndeski, or "generalized Galileon," models. Despite possessing equations of motion of higher order in derivatives, we show that the true propagating degrees of freedom obey well-behaved second-order equations and are thus free from Ostrogradski instabilities, in contrast to standard lore. Remarkably, the covariant versions of the original Galileon Lagrangians-obtained by direct replacement of derivatives with covariant derivatives-belong to this class of theories. These extensions of Horndeski theories exhibit an uncommon, interesting phenomenology: The scalar degree of freedom affects the speed of sound of matter, even when the latter is minimally coupled to gravity.

Treatment of relapsing-remitting multiple sclerosis after 24 doses of natalizumab: evidence from an Italian spontaneous, prospective, and observational study (the TY-STOP Study).

IMPORTANCE: The evaluation of therapeutic choices is needed after 24 doses of natalizumab in patients with multiple sclerosis (MS). OBJECTIVE: To evaluate the effect of therapeutic choices on the mean annualized relapse rate and on magnetic resonance imaging MS activity after 24 doses of natalizumab in patients with relapsing-remitting MS. DESIGN, SETTING, AND PARTICIPANTS: The TY-STOP study, which recruited participants between October 22, 2010, and October 22, 2012, at 8 Italian MS centers (secondary care outpatient clinics) among 124 adult patients who demonstrated no clinical or magnetic resonance imaging MS activity after 24 doses of natalizumab. INTERVENTIONS: Natalizumab, no treatment, interferon beta, glatiramer acetate, or fingolimod. MAIN OUTCOMES AND MEASURES: The primary end point was the mean annualized relapse rate. Statistical analyses were performed in 124 patients with complete follow-up data among 130 patients who were recruited and stratified into study groups. In the intent-to-treat group, the decision was made to continue or interrupt natalizumab after 24 doses. In the as-treated group, natalizumab continuers received natalizumab, natalizumab switchers changed to different therapies, and natalizumab quitters discontinued natalizumab during the study year. RESULTS: No significant differences in demographic or baseline clinical characteristics were found among the study participants. In the intent-to-treat group (n = 124), clinical (P = .004) and radiologic (P = .02) MS activity was significantly lower in patients continuing natalizumab (n = 43) than in patients interrupting natalizumab (n = 81), with a protective effect of natalizumab continuation on both outcomes (odds ratio [OR], 0.33; 95% CI, 0.15-0.70 for clinical activity and OR, 0.35; 95% CI, 0.15-0.79 for radiologic activity). In the as-treated group (n = 124), clinical (P = .003) and radiologic (P = .03) MS activity was significantly lower in natalizumab continuers than in natalizumab switchers or quitters, confirming a protective effect of natalizumab on the risk of relapse in natalizumab continuers compared with natalizumab quitters (OR, 4.40; 95% CI, 1.72-11.23) and natalizumab switchers (OR, 3.28; 95% CI, 0.99-10.79). No disease rebound was observed in natalizumab quitters. After natalizumab discontinuation, 1 patient developed progressive multifocal leukoencephalopathy during the observation period, with complete recovery. CONCLUSIONS AND RELEVANCE: This study provides class III evidence of an increased risk of MS activity resumption after natalizumab discontinuation. Therapy discontinuation after 24 doses in natalizumab-responding patients should be considered only if the risk of progressive multifocal leukoencephalopathy is high and outweighs the benefits of continuing the drug. TRIAL REGISTRATION: Osservatorio Nazionale Sulla Sperimentazione Clinica dei Medicinali No. 131/2010.

Implications of relativity on nonrelativistic Goldstone theorems: gapped excitations at finite charge density.

We adapt the Goldstone theorem to study spontaneous symmetry breaking in relativistic theories at finite charge density. It is customary to treat systems at finite density via nonrelativistic Hamiltonians. Here, we highlight the importance of the underlying relativistic dynamics. This leads to seemingly new results whenever the charge in question is spontaneously broken and does not commute with other broken charges. We find that that the latter interpolate gapped excitations. In contrast, all existing versions of the Goldstone theorem predict the existence of gapless modes. We derive exact nonperturbative expressions for their gaps, in terms of the chemical potential and of the symmetry algebra.

Measuring deviations from a cosmological constant: a field-space parametrization.

Most parametrizations of the dark energy equation of state do not reflect realistic underlying physical models. Here we develop a relatively simple description of dark energy based on the dynamics of a scalar field which is exact in the limit that the equation of state approaches a cosmological constant, assuming some degree of smoothness of the potential. By introducing just two parameters defined in the configuration space of the field, we are able to reproduce a wide class of quintessence models. We examine the observational constraints on these models as compared to linear evolution models and show how priors in the field space translate into priors on observational parameters.

Model for gravitational interaction between dark matter and baryons.

We propose a phenomenological model where the gravitational interaction between dark matter and baryons is suppressed on small, subgalactic scales. We describe the gravitational force by adding a Yukawa contribution to the standard Newtonian potential and show that this interaction scheme is effectively suggested by the available observations of the inner rotation curves of small mass galaxies. Besides helping in interpreting the cuspy profile of dark matter halos observed in N-body simulations, this potential regulates the quantity of baryons within halos of different masses.

Runaway dilaton and equivalence principle violations.

In a recently proposed scenario, where the dilaton decouples while cosmologically attracted towards infinite bare string coupling, its residual interactions can be related to the amplitude of density fluctuations generated during inflation, and are large enough to be detectable through a modest improvement on present tests of free-fall universality. Provided it has significant couplings to either dark matter or dark energy, a runaway dilaton can also induce time variations of the natural "constants" within the reach of near-future experiments.