Table 1 Drug responses in patients with loss- and gain-of-function GABRB3 variants.

From: Gain-of-function and loss-of-function GABRB3 variants lead to distinct clinical phenotypes in patients with developmental and epileptic encephalopathies

 

Seizure freea

Seizure reduction

No effect

Worsening/adverse effects

Loss-of-function GABRB3 patients

Sodium Channel Inhibitorsb

12% (2/17)

5.9% (1/17)

59% (10/17)

24% (4/17)

GABAergic Enhancersc

42% (8/19)

5.3% (1/19)

47% (9/19)

5.3% (1/19)

Carbonic Anhydrase Inhibitorsd

29% (2/7)

29% (2/7)

43% (3/7)

0% (0/7)

Valproate

44% (8/18)

22% (4/18)

28% (5/18)

5.6% (1/18)

Levetiracetam

30% (3/10)

10% (1/10)

60% (6/10)

0% (0/10)

Steroids/Ketogenic Diet

50% (2/4)

0% (0/4)

50% (2/4)

0% (0/4)

Overall

33% (25/75)

12% (9/75)

47% (35/75)

8% (6/75)

Gain-of-function GABRB3 patients

Sodium Channel Inhibitorsb

17% (1/6)

0% (0/6)

83% (5/6)

0% (0/6)

GABAergic Enhancersc

0% (0/12)

17% (2/12)

58% (7/12)

25% (3/12)

Carbonic Anhydrase Inhibitorsd

20% (1/5)

20% (1/5)

40% (2/5)

20% (1/5)

Valproate

0% (0/6)

0% (0/6)

83% (5/6)

17% (1/6)

Levetiracetam

0% (0/9)

11% (1/9)

78% (7/9)

11% (1/9)

Steroids/Ketogenic Diet

20% (1/5)

0% (0/5)

80% (4/5)

0% (1/5)

Overall

7.0% (3/43)

9.3% (4/43)

70% (30/43)

14% (6/43)

  1. aIncludes when used either in monotherapy or polytherapy.
  2. bIncludes carbamazepine, oxcarbazepine, phenytoin, lacosamide and lamotrigine.
  3. cIncludes clobazam, clonazepam, nitrazepam, phenobarbital, stiripentol and vigabatrin.
  4. dIncludes sultiame and topiramate.