Table 1

Timing of interventions and measurements

	Pregnancy	Birth- 2 weeks	Month of life
	Pregnancy	Birth- 2 weeks	1	2	3	4	5	6	7	8	9	10	11	12	15	18
Recruitment, consent	X	X
Enrolment		X
Interventions
A. Nicotinamide intervention
Nicotinamide (or placebo) to mother: daily 0–6 months			X	X	X	X	X	X
Nicotinamide (or placebo) to child: daily 6–12 months									X	X	X	X	X	X	X	X
B. Antimicrobial intervention
Azithromycin single dose to child								X			X			X	X
Nitazoxanide 3 day course to child														X	X
Measurements
A. Mother
Weight: Month 11													X
Height: Month 11													X
Blood								X
Stool								X
Saliva (FUT2 secretor status)									X					X
B. Child
1. Anthropometry
Weight		X	X	X	X	X	X	X	X	X	X	X	X	X	X	X
Length, head circumference, mid-upper arm circ.		X			X			X			X			X	X	X
2. Questionnaire
Education, environment, socioeconomic			X
Illness, treatment, breast feeding, food security			X	X	X	X	X	X	X	X	X	X	X	X	X	X
3. Breast milk: Months 1 and 5
Tryptophan, niacin, nicotinamide, vitamers			X				X
Vitamins			X				X
Protein			X				X
4. Blood
Safety assessment (CMP, CBC in subset)				X						X
Haemoglobin														X		X
IGF-1														X		X
CRP														X		X
Collagen X														X		X
Tryptophan metabolites														X		X
Metabolomics														X		X
5. Stool
Microbiome								X*						X		X
Taqman Array Cards								X*						X*		X
Myeloperoxidase								X						X		X
6. Urine
Metabolomics								X						X		X
7. Saliva
FUT2 secretor status								X
8. Breath
H₂, methane (small intestinal bacterial overgrowth)								X						X		X
9. Developmental testing
Observation of Maternal Child Interaction								X
Malawi Developmental Assessment Tool																X
Bayley Scales of Development																X

*Evaluation also performed two weeks after anti-microbial dose.
CBC, complete blood count; CMP,comprehensive metabolic panel; CRP, C reactive protein; FUT2, fucosyltransferase 2; IGF-1, insulin-like growth factor-1; ITT, intention-to-treat.